I have a couple of Monster Tokens that do not have Enemy Cards that match. the Tokens have the same logo on the front as the Enemy Deck except they are red.

Valley Monster token 84 and 85 do not have enemy cards that match

Those are special monster tokens, and I'm guessing those will get revealed by the exploration deck instead.

If you don't have that card as an exploration card as well, then you need to contact FFG and have them replace the cards for you.