How closely do internships look at classes on transcripts?

I didn't list a research thing at last uni because it didn't end well and honestly resulted in a suspended msdmnr charge for a drunk phone call. I already had one interview based on this resume for an internship and have another one next week.

It was stupid to do but the research thing is listed on my transcript too. I just figured if they found out about how bad I screwed up at my last job I would be out of the running for sure but now I realize I may have screwed up worse and I think I may have to just go with it and try to fly under the radar. Alternatively I could tell them at the interview with the second company but again, I think this would knock me out of the running.

How closely are companies going to look at transcripts for ugrad internships? I could also say the job fell through

Alternatively if I being it up in the interview and then list it when they have me fill in an app, I worry HR (who isn't doing the interview) might zero in on the discrepancy

So yeah, how close are they likely to look and what would be the best way to handle this? Should I just let it slide through? Or just tell them first thing in the interview?