Was this a hey girlie text? And do I tell him?

I’ve been talking with this guy for a few months, went out a few times, hooked up a few times yadayada. We’ll call him Corey. There’s also this other guy who I know from out at the bars and queer events. We’ve had some light flirting when we’ve crossed each others paths, but it’s mostly platonic. We’ll call him Nick. I haven’t been going out to bars and events for the last few months so I haven’t seen Nick in while, but I have been seeing Coreyon little dates and stuff. The day before yesterday i get a DM on instagram from Nick. After some “hey, how you doings”, he sends me a nude! I’m only slightly shocked because while it came out of no where, there is a bit of chemistry between us.

I tell him the nude is hot (it is), but that I’m not looking. He asked me “is because I’m dating someone or am I just not in the mood” To which I reply that I’m not exclusive with anyone right now but that I only have eyes for one person right now. He immediately asked if it’s Corey… Now im shocked, I didn’t even knew they knew each other. And Corey and I aren’t an actual THING, we’ve been out at the bars a few times together but not that much. So I asked Nick how he knew that? He tells me that he was with Corey and some other friends at a comedy show last month and that Corey told him I’d be there. Corey did invite me but I had to cancel because of work. He proceeds to tell me that him and Corey were seeing each other for a bit before but just were having fun.

We chat a little more and agree we should hang out sometime platonically, but I’m left with a few questions… If you knew I was dating Corey, why the seek me? (Maybe he didn’t know for sure? Idk what their conversation was like.) Am I being tested? Do I tell Corey about this exchange? I’m supposed to see him later today for dinner. What is the right thing to do? I don’t want there to be any drama, and I don’t think there is any. Nicks gesture could have been, and I believe is, entirely innocent, but if I don’t tell Corey, am I being secretive?

I also don’t want to get in the way of their friendship…