I was in the bakery in Israel where Lakewood makes the oat matzoh, they have a guy that comes to test the air to make sure there's no gluten. Oat is also the first batch of the year so you don't have other flour in the main bakery room yet.
Oat dough is extremely delicate and there is a lot of waste even with machine matzoh. I'm sure that's part of the reason it's so pricey.