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Amber Portwood’s Fiancé Matt Baier Takes Lie Detector Test Amid Cheating Scandal The ‘Teen Mom’ star dumped him after he failed the polygraph in front of cameras!

Amber Portwood kicked Matt Baier to the curb after he failed a lie detector test – and the entire breakup was caught on camera! RadarOnline.com was the first to exclusively report that the polygraph was filmed for Teen Mom OG.

In a sneak peek for the season finale, Matt Baier is seen taking a lie detector test.

“Have you had any sexual communications with other women?” the administrator of the test asked Baier.

Portwood then screamed, “I’m about to freak out, I’m about to freak out!”

In another clip, Portwood says, “I told him if he ever cheats on me I’ll leave.”

The trailer then cuts to a man holding Portwood as she tries to attack Baier while screaming, ‘You f**king b***h!”

On last week’s episode, Portwood learned that Baier has been texting another woman.

“There’s fake f*****g text messages supposedly,” Portwood said of messages that emerged between Baier and another woman on social media. “Talking to someone else like a year and a half ago. I told him in the car we need a break. This is too much. It just keeps making me doubt everything. I need to figure out what’s going on with all this s**t.”

Portwood called off her engagement to Baier when he failed a lie detector test about the text messages in May.

“Amber says he didn’t pass,” a source close to the mom of Leah, 7, told Radar. “It was filmed by MTV, so it will all play out of Teen Mom.”

Although they were “still living together” at the time, she revealed over Instagram live earlier this month that they are not together.

But there is still hope for the couple, as they are currently in Los Angeles together. Radar exclusively reported that they are filming the upcoming season of Marriage Bootcamp: Reality Stars.

The Ashley’s Reality Roundup was the first to report on the split.

The TMOG season finale airs Monday at 9/8c on MTV.

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