Is it possible to get a STI this way or his he lying??

So I have a friend that suspects her husband is cheating. Her husband works on a pipeline that does 2 random drug tests during the new year. He’s been there for about 15 years. He’s been using marijuana (medically) for anxiety & ptsd for about 6 years now. The job changed their policy due to the legalization of marijuana about 5 years ago, so his drug tests are for hard drugs & if marijuana is found he wouldn’t be terminated. His records also show that he takes medical marijuana. Unfortunately the owner passed away & now his eldest son & youngest brother are the new owners, who don’t agree with marijuana in any form, so his boss gave him a heads up the day of the drug test & told him to have someone to pee for him on the “safe” side because they’ve lost a lot of good employees due to the new owners disregarding their policy & terminating because of their judgements. They’ve been randomly drug testing anyone who have tested positive before. The guy who pissed in a tube for him works there also, he’s about 20. Her husband had the tube in his pants, the pee wasted a little & got on his genitals & butt. This happened maybe 2 weeks ago, she said they had sex the day after his drug test & she had an annual pap + full panel done about 3 days after his drug test. She got her results back that following week saying she have chlamydia, since they’re married they suggested her husband come in & get a rapid test & he too came back with chlamydia. They did a full panel on him after those results & he’s waiting on the results now. He told her he might’ve got it from the pee that wasted & since she had already known about that incident, she believed it but now she doesn’t. She think he’s cheating, but doesn’t have any proof but he’s been taking private calls when they’ve never done that & he’s been lying about where he’s going (they openly have each other’s location for safety & he tells her the maps are wrong, he wasn’t there- he was there). What are your thoughts?? Can he get a STI that way or his he lying & maybe cheating?

EDIT: THE NURSE TOLD HER IT WAS POSSIBLE IF THE OTHER GUY WAS INFECTED, SINCE URINE & SEMEN LEAVES THROUGH THE URETHRA. THE INFECTED URINE COULD PASS ON A STI OF IT TOUCHES THE TOP OF THE PENIS/URETHRA HOLE, NOT THE SHAFT. JUST LIKE IF A GUY WAS TO PEE IN YOUR MOUTH INFECTED, YOU’D GET INFECTED TOO.. ARE YOU SAYING THEY WERE WRONG?