I'm planning on back it in the next two days. Ever since I got Adventures in Middle-Earth 5E and heard we initially lost out on a Moria book when Cubicle 7 lost the license, I was bummed out that we wouldn't get it OR the Balrog. Now we are getting it finally, even if its with a different version of the 5E take on LoTRs.
Granted, I DO have Kobold Press's Tome of Beast Books if I had to find a sufficiently HIGH CR monster to reskin if I needed the balrog for the original AiME book rules being used.