Thanks for all your thoughts. It's been asked what our DM did and I wanted to hear all your great ideas before putting it out.
First, the DM knew the player was completely okay with spending a bit of time stoned and having a cool story about coming back.
So the DM had one of the ways we had researched come through with an alchemical solution - that needed one last ingredient: wyvern blood. For a party of 6th level, Wyverns would be a fun fight - especially since we we're at our strongest against flying foes.
He put two sources in quick (wall clock time) reach. Wyverns at an oasis we could find out about and kill, or some wyvern blood at the queen's apothecary. The queen whom we had antagonized last session, so we would have been crawling back to her OR a heist. He estimated 30 minutes of our 6 hour session to have either one worked out quickly, with a heist taking longer.
We rolled really poorly (and didn't ask the right people which would have been an easier DC) trying to find about wyverns. We did find out about the queen's apothecary. We also came up with another idea he didn't think of but he rolled with when we pursued it, which was a alchemist might have one. We found one, but ti would basically have taken all of the coin treasure we had accumulated since the start of the campaign, a scroll of silence, a dragon tooth and a unicorn horn (the items were ones we had to get the price down to just "everything we had").
Would have been done within that 30 minutes ... except that our party "leader", a barbarian who thinks himself king of a forgotten land, killed the alchemist. The scream was heard outside the shop, someone outside called for the guard, and suddenly whistles started to blow.
This turned into a two hour event as one part of the party distracts the guard and leads them off elsewhere in the city (mind you, we had antagonized the queen the day before - this could have been really bad if caught), the others broke into his storeroom and found the wyvern blood then tried to escape with bystanders and guard about. Disapproving of the random killing our cleric ended up reviving him (using about half our stash of diamonds we had gotten in case to use on us) and convinced him she saved him. (The barbarian hadn't been seen with us before - it was the bard and the cleric who had found the alchemist - we had split up trying to get the blood).
All in all it was 2 hours of session to escape, but the new player has quite the story to tell about how he got turned back to flesh, which he enjoyed.