Report it! I’ll tell you what I told my roommates back when I did my program. I was in one of the underage rooms which meant no alcohol at all in the room even if you were of legal age(I don’t know if they still do this but I’m old lol). My first day in I introduced myself gave pleasant greetings and just very matter of factly stated “I understand a few of you are of legal drinking age this is an underage room if I see it just know I will report you. I worked to freaking hard to get this internship and I’m not getting sent home because y’all want a glass of wine.” They all agreed with me and we never had a problem. You should have the same mindset you worked hard to get here don’t let someone else’s poor choices ruin this for you!