If you complete the 'proof of a warrior' that's given by Rhot you get a spear that deals damage to the slimes.
The witch recipes have to be manually brewed to be learnt, the mini poem the day witch recites is the ingredients order and the same for the night witch drawing. You kinda have to guess what the ingredients are but it's easy to do that, since they're not extremely rare or anything.
You have to take the raptor back at night since the witch at night is different from the witch at daytime. Unless you accidentally aborted the mission if that's the case I have no idea of how to get it back.