Wait, did Doc Brown always know Marty would show up?

Okay, so I just watched Back to the Future for like, the millionth time? And something struck me. Doc Brown is kinda sus, right? Think about it. He's got this whole setup ready to go, right? Like, the DeLorean is prepped, programmed for a specific date (November 5, 1955, the day he invented time travel, duh). But how did he know someone would be there to use it? Like, yeah, he invites Marty, but what if Marty had the sniffles that night? Would Doc just... try and time travel alone? I don't buy it. My theory? Doc Brown maybe... already came back from the future before we see him in the movie. Maybe he saw Marty's picture at the Enchantment Under the Sea dance – that's a pretty iconic photo, right? Maybe he even subtly manipulated events to ensure Marty would be the one to hang out with him that night. He's an eccentric genius, he's probably got some low-level mind control tech lying around, I dunno. He's definitely got the plutonium connections. And why plutonium anyway? It just seems way too convenient that everything lines up so perfectly. Doc's timing with the Libyan terrorists is insane. Like, he knew they were coming, he just needed Marty to be in the DeLorean to push things forward. Maybe he needed the desperation push? I know, I know, it sounds crazy. But think about it! Time travel messes with your brain, man. Maybe Doc's playing a way longer game than we realize. Maybe he's just trying to keep the timeline stable... or maybe he's trying to mess with it just a little for science. What do you guys think? Am I onto something, or have I just spent way too many nights mainlining bad sci-fi... again? LOL