Walt was talking into Jesse's phone. I suppose these phones can be set to record the conversation. I also suppose it's possible that Jesse, even if Hank had Jesse's phone in his pocket, could call from another phone and play back the recording, just as he could call his own number and playback his messages/voicemail. Also, Jesse also knows that the memory card with his confession is at Hank's house. I don't think he knows that Hank had copied it onto another memory card while he was in the restroom.
Yes, it is implausible that Jesse survives. Yes, the shootout was unrealistic. The plotting has become very sketchy and arbitrary. Yes, it is plausible that someone with 385 gallons of money and no explanation for it is done. If the DEA can't make it stick, the IRS will. No, Saul would not have been be able to work his magic, nor would Walt have been able to go gadding about free from intense police observation.
No, Skylar will not reconcile with Marie. Marie in fact is the next target, and should die in the next episode, and that may finally turn Skylar off the money. Yes, Jack will know that Hank and Gomez were working by themselves, because if it was an official operation the helicopter would have spotted their convoy. So, yes, Jack's going to the Shrader house.
Yes, Walt will try to use the DVD against dead Hank. A corpse has a lot less defensive power, but even so, it would be preposterous if the DEA buys into Walt's little drama.
What does Hank's demise mean in story telling terms? The true hero, a flawed man but a good one, is still a loser, who snatches ignominious defeat from the jaws of victory.
In Walt's morally perverted eyes, Jesse has betrayed him and he can no more forgive Jesse than he could have been satisfied to die as a loving husband and devoted father, which is to say, a loser. Walt preferred being a winner (as does much of the audience,) to be a good man. Walt is the antihero. As the antivillain, Jesse's confession is a step toward redemption. Although the show chose to minimize it, Jesse's confession is also a judgment on Walt. The viewer is given (dimly, clumsily) a starkly dramatic choice between Walt and Jesse.
Like Hank, Jesse is still a loser. On one level of course many in the audience identify with Walt the winner. I suppose they could not accept Jesse as a winner, a perversion of the natural order in which only the strong like Walt win. Weaklings like Jesse are just crazy.
Here at the end the series cannot finesse its decision about what it values in Walt/Jesse/Hank.
I suppose it's possible that Walt is skipping witness relocation in New Hampshire, not surfacing from his own escape.
PS I think the Todd thing isn't a bit sincere. But the soft, romantic approach to older superiors worked out in prison pretty well. Todd's a practical young man, he sticks with what he knows.