(They each put the top card of their library into their graveyard.) If you are instructed to put a card into your graveyard from your library without using the word "mill," (by the effect of Rowan's Grim Search from Wilds of Eldraine , for example), Raul's first ability won't allow you to cast it
Hopefully, by the time we're done, we'll have a better idea of just why these cards are so important, what decks they fight against, and why, when you are building a deck, you should be including these effects somewhere in your 75
After being used, Malevolent Hermit can be brought back as Benevolent Geist, preventing your own noncreature spells from being countered
I do not know if these interlopers can stop him
I do worry that there might be a bit too much tracking for a new player here, with multiple cards having multiple different types of counters, and a lot of moving counters back and forth between permanents