As this Bank Holiday weekend drew to a soggy close, the story begun to emerge of how 80 unemployed people from Bristol, Bath and Plymouth were bussed to London to "work" as stewards for Sunday’s Diamond Jubilee river pageant.

Fifty of them were on "apprenticeships" and would be paid £2.80 an hour. The rest were on the Government’s Work Programme, and they’d been led to believe by Close Protection UK, the company they were providing stewarding services for, that they’d be paid for the work. Some had even signed off in anticipation. But then Tomorrow’s People, the charity running the Work Programme in their area, told them it was ‘work experience’ and they wouldn’t be paid. Some of them didn’t find this out until they boarded the coach to London, with the tents and sleeping bags they’d been told to bring with them. They arrived in London at 3am Sunday morning, and were left by the roadside. 20 minutes later they were shown under London Bridge and told that’s where they could camp until their shifts began at 5.30am. But they couldn’t pitch their tents on the concrete and it was too cold and wet to sleep. Their "work experience" consisted of standing for hours in the pouring rain, shivering in the inadequate clothing provided, doing virtually nothing as they’d not really been told what to do. A marked contrast to the splendour of the pageantry itself.

The director of Close Protection, Mary Prince, by the way, initially said that the "London Bridge" was a mistake, that the coaches shouldn’t have driven off and left them there. But in that case, why were they told to bring tents? And what were the drivers supposed to have done with them? Mary Prince also said that the only people who weren’t paid were ‘the ones who didn’t want to be paid’ because they’d lose their benefits.

The steward I spoke to yesterday had been on the Work Programme with Tomorrow’s People for a year, but apart from occasional sessions with an adviser (she’s on her third, as they keep leaving) ‘nothing had happened’ until March this year when she was put on the NVQ Level 2 in stewarding. She’d already done a stint of unpaid work experience in late March. I don’t think she was much impressed by the quality of training but she’d stuck with it, hoping to get paid work. Close Protection had said they’d pay the jubilee stewards £450, and it would lead to well-paid stewarding work at the Olympics. But she ended up calling home in tears and being rescued by a relative, after 36 hours without sleep, soaking wet and without being paid a penny for it.

Those are the basic facts that I’ve been told, and that have been reported in the Guardian and on a blog by Eddie Gillard, but the real questions remain to be answered. Here are just some of them.

Is the Work Programme fit for purpose? Is it actually providing training and work experience that will equip people for the world of work, and if not, what is the DWP actually paying charities such as Tomorrow’s People to do? What monitoring is there of the Work Programme; what scrutiny of its outcomes? Where do you draw the line between giving people work experience they would otherwise not have had, and exploiting them as cheap or unpaid labour? Are these real apprenticeships? (Polly Toynbee among others has written about how this government’s much vaunted apprenticeships are simply rebadged Train to Gain or other lesser schemes, and not what would have in the past have been regarded as proper apprentice training).

What was the relationship between Tomorrow’s People and Close Protection UK? £1.5 million was allocated to pay for security at the jubilee pageant. How much of this went to Close Protection UK? How much, if any, went to Tomorrow’s People or wasn’t it a financial arrangement? When Close Protection UK were awarded the stewarding contract, was this on the basis that they’d use unpaid labour (and if so, were the organisers happy with this?) Or were the organisers led to believe that the stewards would be paid, and the contract price fixed accordingly?

Interestingly Close Protection UK says on its website, specifically under ‘Event Staff’: “Here at CPUK we pride ourselves on our reputation within the industry and therefore only provide the best and most competent event staff. All of our staff are trained to NVQ Level 2 in spectator safety (supervisors trained to Level 3) and all are SIA licensed in door supervision.”

The steward I spoke to hasn’t yet got her NVQ Level 2 (and doesn’t know if she will now, having walked out on the jubilee ‘training’). Some on the coach to London had got their SIA licence, but others hadn’t. So did Close Protection lead the pageant organisers to believe they were hiring – and paying for - ‘the best and most competent’?

Questions are also being asked about the security implications of hiring unqualified inexperienced staff for such a high profile occasion, by Lord Prescott, who has written to the Home Secretary, and my Labour colleague Bill Esterson who has tabled some written parliamentary questions. John Prescott has asked Theresa May to investigate whether Close Protection UK has broken the Security Industry Authority’s approved contractor status terms, including its ‘fit and proper person’ criteria, and whether it should still be allowed to provide stewarding services at the Olympics.

There are also concerns about the financial standing of Close Protection UK, whose net worth is currently shown by Companies House at £-185,861. The director Mary Prince has dissolved another six companies in the last six years.

Over the coming days more will be revealed, no doubt. I hope this triggers a wider debate about the use of workfare and Work Programme participants on "work experience" as a substitute for paid labour, and the exploitation of the scheme by companies who could and should pay a decent wage instead. Not to mention the exploitation of the "volunteers" who live in fear of being sanctioned or refused paid work if they turn down such opportunities. We also need to ‘follow the money’. Who was paid what, and what for, and why weren’t more questions asked about who and what and why? Watch this space, as they say.

Kerry McCarthy is the Labour MP for Bristol East and shadow foreign minister.