[Zeke]

I'm reluctant to address this as IDK, as you don't know, exactly what lacquer it is. Only because I keep Mohawk Blender Flow Out on hand, I would spray that on it just to see. The thing about just water damage on lacquer is that it is easily healed. But generally I avoid anything that requires rubbing or brushing unless it's not lacquer.

If the finish is catalyzed lacquer, the Flow Out won't dissolve the finish but it won't hurt it either. What it will do is tell you what the white does wetted. If the color comes back while wet, you can go ahead with a pre cat lacquer.

You could test with naphtha but believe it or not, you're adding an oil. If you use acetone you are going to physically disturb the surface. That could turn out good or bad, so testing on the bottom is reccommended.

That said, the last thing you want to do is capture the white with some sealer. You'll end up stripping the whole surface.

One more note: only you know what has been put on these over the years like wax or dusting spray. It's paramount that all that be removed w/o carrying any of it into the damaged area.