Polygraph test?

My husband was caught with another woman in a hotel room. He swears they’re only friends and we’re only drinking. I’m no idiot I’m not buying it. So he agreed on a polygraph test. I don’t know what’s the point my mind is made but I just want to get some kind of satisfaction of him trying to not lose me so I can keep some self worth at this time. Please don’t judge my life is a mess right now I feel like I’m gonna lose it. 😞😞