Thankfully I've never had to deal with fleas. Ick. Hopefully the short time he was inside helps prevent them from hanging out on your couch. Kudo's to you for scooping him up! I'll only ever rescue I think, I just find it so much more rewarding. Good luck wearing down the hubs! I've been working on Jordan for 3 years now to get a second dog and he is NOT budging, lol.
PS~If he looks like that white guy, he's DEF got Shiba Inu in him. I love Shiba's.