Girlfriend says yes to MFM but only with trusted friends [Cuckold’s perspective]

Hey guys, both 21, together 6 years since high school. She’s slim, 1.60m, fair skin, glasses, pretty. I’m her only real experience. She had one bf before me, did blowjobs and stuff but says no penetration (tried like 4 times but didn’t happen). Imagining her doing that young made me jealous af but also super horny. For like 3 years I’ve been fantasizing hard about MFM threesome or watching her with another guy, preferably bigger than me. We’ve used toys a lot: her fave vibrators, and bigger dildos. One 22cm goes almost all in, the 25cm thicker one only halfway but with tons of lube it goes in more than I expected, shocked me. At 18 I told her about the threesome idea and she said right away yes but only with someone we trust. There was this one time at a friend’s house (guy from middle school, they liked each other back then but nothing happened) just the three of us, I saw in her face she wanted to bring it up but chickened out. Recently brought it up again and same thing: yes, but with that friend or my other close friends. I don’t love the idea of it being my friends cuz rumors can spread, drama later, etc. I’d rather a stranger or someone we never see again. So do you think she’s just saying “only with trusted friends” to softly reject it without hurting me? Or does she actually wanna fuck them but needs that trust/safety thing? Tbh it would still turn me on a lot even if it’s my friend, the jealousy + horniness is intense. But the practical side scares me. Anyone been here? How did you deal with the “only known people” rule? Thanks for any real advice.