Can the bot manage roles above its own?

No. Discord only lets a bot manage roles below its highest role, and Dungeon Keeper also checks the hierarchy for the member running the command.

Do temporary roles need manual cleanup?

No. Temporary roles expire automatically at the end of the duration you set.

Grant, remove and expire roles automatically. Dungeon Keeper handles the repetitive role work so staff do not have to.

Auto roles
Give members roles the moment they join with /auto-role, including extra roles alongside the main one.
Rejoin role restore
Restore a member's roles when they come back to the server.
Temporary roles
Assign a role for a set time with /temp-role and it is removed on its own when the time is up.
Reaction roles
Let members pick roles by reacting to a message, with optional roles to remove and restore.
Role restrictions
Stop one role from being granted alongside another with /restrict-role.

Can the bot manage roles above its own?: No. Discord only lets a bot manage roles below its highest role, and Dungeon Keeper also checks the hierarchy for the member running the command.
Do temporary roles need manual cleanup?: No. Temporary roles expire automatically at the end of the duration you set.