As to resources found during the mission, my search-fu is weak at the moment, but Mike Brock, the former campaign coordinator, had ruled that players may use any resources they find during the course of the adventure as soon as they earn them, including prestige. That means if completing the primary objective gives the character just enough prestige to pay for the raise, they can spend it just as soon as they can get somewhere to get it cast.
Do you have a link to that?
The Season 8 Guide says that you cannot sell equipment found during the scenario but that you can use Chronicle rewards that you have earned which is a rather fuzzy way of putting it.
Players are encouraged to share their physical resources in order to resolve any and all conditions. They may not pool Prestige Points, even if they’re from the same faction. Characters can also sell off gear, including the dead character’s gear, at 50% of its listed value to raise money to purchase a spell that will resolve the condition, though they can only do so in a settlement and they cannot sell off any items found during the current adventure that they haven’t purchased. Characters can use the rewards from the Chronicle sheet they earned in order to resolve any conditions. Characters who die during an adventure and are raised receive full XP for that adventure, as long asthey completed at least three encounters.