If Minato marks Obito, I don't see what's stopping Minato from just teleporting back and forth between kamui and hitting his opponents with TBB everytime he teleports back. Eventually they would bore a hole through his opponent's defense. Obito would just slip through all his opponent's attacks and materialize only so Minato can teleport to him
No Bijuu Dama Minato has is scratching Naruto and Sasuke's combined defense, so unless he makes something stronger, using the same attack over and over again isn't going to help. Minato still has to fire his Bijuu Dama, so that gives Naruto time to charge one up enhanced with Senjutsu, whether or not he gets to fire it doesn't really matter since the force from Minato's will cause it to blow, which destroys Obito's Susanoo (If he's using it) and Minato's Avatar while Naruto and Sasuke take damage, but survive.
-Nobody here can react to FTG with an attack that breaches Kurama Avatar before Minato fires TBB and teleports back to kamui. He can charge up the TBB in kamui so its prep time is irrelevant.
They don't need to react to Hiraishin. The only need to react to Minato firing his Bijuu Dama. SS can catch it, Naruto can overpower it, Kakashi can tank it.
-Unless somebody can land a hit on Obito the moment he materializes (before Minato teleports to him) with an attack strong enough to breach PS, they can potentially beat everyone except maybe Kakashi who also has kamui.
Absolutely not. Minato can fire any amount of Bijuu Dama he wants. Naruto and Sasuke's combo Avatar tanks it, or they overpower said Bijuu Dama with their own. Kakashi outright tanks it with his Rikudo chakra enhanced Perfect Susanoo, or he phases right through it. Shinsuusenju would catch it, since Minato can teleport to Obito all he wants, it doesn't change the fact that he has to actually fire it after he's teleported back to the real world.
