You need a residual insecticide its the common clothes moth larva that could do the damage, the curing chemical will probably stop them for a while, moth balls will stink and moth traps only trap males as a monitoring system so won't work, cedar wood is supposed to deter them you could try having a plack made out of that, there aren't many residual insecticide that last more than a few weeks other than woodworm treatments and they might affect the look of the velvet.
Hope that helps a little Jake