Nope not Vincent. He's the 2nd to last character found, but how is part of the second found of something else? Also, my hint explained that my riddle is true if you've found everything in the field in the regular quest (so, no sidequests and hence Vincent is wrong under that logic,too) and haven't failed anything.

Since nobody is coming close, I might at well give everyone a hint. It's someTHING you FIND. So's the other THING. There something that you find that's the 2nd thing you've found non-randomly,then if you complete the game w/o missing anything in the main quests, you will find the other thing that's 2nd to last of something more specific, which is "part" of the first thing.