Do these nudibranches only eat monti's and Anacropora or is it their corals of choice?

I am currently working on getting rid of them, and have started moving my monti corals to a QT tank.

However, I want to make sure if I QT my monti's, the nudibranches that remain in my DT will starve to death.

If so, how long will it take?

Of course I am trying to get out most of the nudibraches during the coral removal, but I have to be realistic and assume some will fall off or be missed in the process.

I am trying to avoid dosing my DT with levamisole, but that may be the only option depending on their ability to survive.