Yawie Meat Bug

[Arcanestomper]

I killed the final boss, but I didn't have a chance to collect the meat before the cutscene moved me on. I figured that was just how it worked that time, but then I found there was a recipe that required meat from the boss. So clearly that wasn't supposed to happen.

[Sir Ulysses III]

You can go back to where you killed the boss to collect the meat.

[Skyler]

What that guy said ^^ and I strongly recommend you visit all areas at least a few times if you're a completionist (yes, even some of the puzzle rooms). There are several fish and other goodies you wouldn't otherwise find.

[jibi]

the path to the yawie is blocked
after the 3 fire geysers with 2 snails, it's blocked by rocks

[Nozbot]

You don't need to go that way. You can head to the right as soon as you enter the control room using the snail to open the gate. It's where you battled the boss.