Well to clarify the whole week thing at the beginning. I did read most of part 1 (up to the Kimimaro fight with Lee) in around a month and a half, and over time I just got into the manga just like when I had read it the first time. So sorry about the Typo.
As to the whole "somehow survives" situation, I too believe that what you just said would be the most natural and realistic approach to the story. My thoughts on this started after I read the fight but ALSO when moments later I stumbled upon a Naruto What-if about Minato surviving Obito's onslaught.
Also, thought do take this with a grain of salt since I don't know if this is considered filler or a retcon but, when Obito met Nagato, Yahiko and Konan he was still depicted as white mask, angsty Obito, plus I also assumed that Minato can't simply start a manhunt alongside Fugaku, Kakashi, Jiraiya and Hiruzen since, as Hokage he'd have take care of the economic impact with Konoha's destruction, assign missions, tell the council about his theory and eventually start to formulate a plan to capture Obito.
Just this would take at least a few years to sort out giving Obito time to prepare.
I also assumed that Zetsu would tell Obito to be extra careful since Minato is still alive and currently hunting him alongside Konoha's strongest. Now we can all agree that Obito isn't dumb, he'd know about the mark on his back and try to find a solution to continue working on the Eye Of the Moon plan, telling Zetsu to be Nagato's intel man when it comes to recruiting new Akatsuki members if Minato catches him isn't something too farfetched to say.
My only uncertainties would be if:
- Orochimaru could even leave the village alive
-If Hiruzen stays back in order to work as Hokage while Minato and co. hunt Obito
-Who would Zetsu see as strong enough to consider recruiting
-How would Danzo's plot to re-build Konoha go without the Uchiha being suspicious for the attack, a possibility of Orochimaru being dead to begin with and with the Kyuubi being under constant protection from THE Yellow Flash, Konoha's biggest reason as to why they won the Third Great Ninja War in the first place.