Bill Tindall
Rule one of antique conservation- Do no harm. The risk of irreversibly screwing up the case is high. Don't proceed until you know what the camera case is made from. And then proceed only if you, or an expert, knows what won't damage the case. Lacquer solvent is a mixture of several solvents and one of them is likely to be a good solvent for most plastics. Even if the case is leather it will be a coated leather and a solvent may remove the coating, and color and maybe even texture.

Something may have softened the case material and made it sticky. Presumably the felt didn't get sticky on its own. You need to know what softened the case to reverse the problem. Maybe the case is some plastic made to look like leather. Many plastics are plasticized with a nonvolatile solvent. If the stuff gets hot plasticizer can bloom to the surface and make the surface sticky. In this case, and probably in any case, the felt fibers are now fused into the case material. It is not clear how they can be gotten back out without messing up the case material.