I work with lasers and optical surfaces, so I have experience in this kind of stuff as well and not only cleaning the Form 2 but some way more sensitive surfaces. Acetone and optical cleaning pads are the way to go, unless the surface you’re cleaning can’t take acetone (Formlabs’ mirrors and glass show no issues in that regard), in which case another quick drying solvent is recommended.
The main reason why Formlabs doesn’t recommend anything else than IPA, I think, is that it’s the least risky solvent because it can’t damage or dissolve anything on the printer except the orange plastics but even then a small quantities of IPA won’t cloud it or anything.
See this page for more details (in particular the “Drop and Drag Method” which is the best method to clean the galvo mirrors in my experience :
I tend to use IPA when there are big things to clean, but I always finish off with a drag and drop operation with acetone.