The theoretical answer is yes, but there are a couple of potential problems.
While you will be able to sand out the lint, you’re no longer going to have an even surface. Even using subsequent grits of sandpaper to achieve a final glossy shine, I would expect you’re going to have a noticeable dent on your glossy surface. You can try adding resin to just part of the painting, but I have found it’s going to be difficult to get it even with the resin you have already poured.
If you wanted to try sanding first, I would suggest sanding as small an area as possible, then trying something like our Novus polishing kit https://shop.resinobsession.com/collections/tools-and-supplies/products/novus-resin-polishing-kit to shine up that one spot. It won’t look as shiny as a coat of resin, but depending on how close someone is going to be to the art, they may not notice.
If that doesn’t work after sanding, then I’m afraid another coat of resin is the only way to go.