Can you look at each other's deceased characters to see how many points they are worth? I would assume so. I say yes.
Deceased pile? There is no "deceased pile" in Gloom. Deceased characters stay on the table, in the same place they were at the beginning of the game.
Therefore anyone can see how much they are worth, as easily as the living characters.
Most certainly you can look at each others deceased characters. There are a several cards that let you swap Untimely Death cards from one character to another or affect the pathos points of dead characters. Not being able to see which of your opponent's characters are worth the most points would make these cards useless.