Subway (1985) - Was Fred ACTUALLY living in the Metro the whole time?!

Okay, horror fam, I know this isn't straight-up horror, but "Subway" (1985) has that gritty, surreal edge that totally scratches the same itch for me. I've been rewatching it (like, for the millionth time lol) and I've been thinking about Fred (Christopher Lambert). We see him rob this dude and flee into the Metro, but hear me out: what if he wasn't fleeing into the Metro, but back into it? Like, what if he was already living there? Think about it. He knows the tunnels way too well, he slips into this underground world seamlessly, and he's got this instant rapport with all the other weirdos down there. Plus, his motivation for stealing the documents feels kinda weak, right? It's almost like a plot device to get him where he needs to be: back in his element. And that random drum set he's playing as the movie ends??? Did the thugs leave that there?! I don't think so. It's like he's a mythical creature, a Metro-dwelling imp who occasionally surfaces to mess with the 'real' world before retreating back to his labyrinth. Héléna (Isabelle Adjani) isn't really a love interest, more like a brief glimpse of the surface pulling at him before he ultimately rejects it. Maybe I'm reading too much into it (I tend to, haha), but I think there's something to the idea of Fred being less of a fugitive and more of a permanent resident, a king in his underground kingdom. What do you guys think? Am I way off base, or is there some metro-magic hiding in plain sight?