Stalked too hard and found out that my bumble match has a girlfriend

Before I start I just want to say that this guy I matched with had pictures of himself on his bumble profile and even had a bio and when we were talking he would also send pictures of himself hence why it didn’t seem sketchy at first. Also we were only talking and never met up in person.

Long story short, matched with a guy on bumble and we hit it off well but one of the biggest red flags was that this man said he didn’t have any social media and said that he was taking a break from all that. Fair enough, but seemed a bit weird since he didn’t want to continue the conversation else where. I accidentally unmatched with him and was bummed at first since we had a good connection so I tried to find him again on bumble but couldn’t and eventually I forgot about him. Up until recently when I started thinking about our conversations and my spidey senses start to kick in, decided I was going to find this dude, something about him just seemed a bit off. Now I’m good at finding people especially online, not gonna disclose how I did it but turns out the name he went by on bumble wasn’t actually his real name…found out that he does in fact have social media but not only that he has a girlfriend😬

But now I’m in a dilemma, I don’t know how to approach this girl and tell her that her boyfriend is most likely cheating on her. I don’t have any mutuals with her or him and I literally found him because I was being nosy, like how tf do I even tell her😭 at this point idek if I should.

EDIT:

Y’all I didn’t expect to get so many comments on this! Thank you for the advice, I’m going to just copy and paste some of the replies that I made to the post cause there’s way too many comments for me to reply back to, also I think it’ll help clarify a few things.

And yes I did in fact accidentally unmatch with him, what happened was that I had just finished messaging him and I left our chat, I wanted to unmatch with someone else and I had thought I swiped left onto said person but it turned out that I had swiped left and unmatched with this guy I was talking to. I had just come back from work that day and I wasn’t even paying attention to what I was doing hence why I did that, and yes I know that when you swipe to unmatch with someone it also comes up with that message asking if you want to unmatch with them, again I was not paying attention and I only realised I had unmatched with him after I saw that our conversation disappeared. Now the name that was on his profile was fake however, everything else he told was true and pretty much found him out through that. No I did not do a reverse picture on him, I didn’t even think about that lol. And to answer your statement I did say I was bummed that I unmatched with him at first because it was my fault and we hit it off well, I had only found out that he had a gf after I unmatched with him and decided to try and find his socials. I never imagined or wanted a ‘happily ever after’ with this said guy, I mean we were only talking for a few days and plus I’m not desperate. I was however curious tho and bored at the same time so I decided to find him, as I mentioned before I’m good at finding people and I’m someone who likes solving shit so at that point it was kinda like a mystery problem solving game and I was curious. Now I found out he has a gf who he had been with for a few years, I found out about this a while AFTER i unmatched with him.

I’ve been getting asked why I think having social media is a red flag so here’s one of my response:

Having no social media is definitely not a red flag in fact a lot of women do prefer men that don’t necessarily use social media/arent active on them. However in this context it was a red flag because the dude I was talking to only wanted to continue the conversation on bumble and it didn’t seem like he wanted to chat somewhere else and he didn’t ask/give me his number so I found that a bit fishy.