One reason I aimed to start with a bigger group... room for attrition, if people left the game. Even if you end up with a party imbalance, story trumps stats, and I can adjust difficulty on the fly.Yay for first session! Boo that people didn't make it. Good luck with forming a stable party.
Mistakes happen. I wouldn't assume someone 'ghosted' the first session rather than actually forgot. That said, in this situation, it does sound like he isn't all that engaged with the game anyway - so it's no wonder he forgot, it that's what he truly did.Personally, I would not re-invite someone who ghosted the first session. I just don't see that sort of relationship ending well.