The reason you didn't get a deal with the devil even though you had 100% chance was bc the boss fight was in a tiny room (I think) I've seen this happen before, there's something about the skinny hallway rooms that glitch the devil's doorway from showing up where you can enter
The other soul fragment is in the Hush fight, but I know that you're on vacation Hutts and all this is pre-recorded so it doesn't matter what I said. Have fune on vacation Hutts
On the second floor room where you fought dingle there is a glitch where you cant get a devil deal becuse the room is not able to show up, happend to me on a lost run and didnt get it, think that is the case :Y
Fate's reward is just too slow to be reliable, it also appears in golden chests (The same pool that could have given you Cricket's head). Brother bobby is faster (Helpful keeping enemies away) and it is part of the Conjoined transformation. PS: Sorry if it sounds rude, that's not my intention at all xD.