Could I boil rose milk?
I assume you are talking about using raw (unpasteurized) milk; and want to make it safe for drinking.

I think you can boil it with the rose essence in it. It should not make a difference either way.

At worse it will taste cooked.

This link will show two ways to pasteurize the milk, either at low or high temperature.

https://www.livestrong.com/article/528722-should-i-boil-raw-milk/