LOS ANGELES — When Humble Lukanga was studying finance at the University of New Mexico, he read about the large number of pro athletes who went broke in retirement. Lukanga knew, on the surface, that he had little in common with linebackers and power forwards. He had spent his early childhood in Uganda, merely trying to survive.

But he felt that he could relate to many of them on one important level.

“I couldn’t imagine escaping poverty and then going back,” he said in an interview, one of only a few the normally circumspect Lukanga has given. “So I became almost obsessed with this epidemic that nobody was caring about.”

It was an obsession that recently helped him rescue Lonzo Ball of the Los Angeles Lakers from potential ruin. In the process, Lukanga, a financial adviser with a growing reputation in Hollywood as a behind-the-scenes power broker and sage, found himself in an unfamiliar role: whistle-blower.

Last fall, Lukanga was doing Ball’s accounting when he discovered that about $1.5 million was missing from Ball’s personal and business accounts. Lukanga alerted Ball, who has since sued Alan Foster, a business partner and family friend, for more than $2 million in damages as part of a lawsuit that alleges that Foster embezzled money from Ball and Big Baller Brand, the sneaker company that Ball co-founded.