I'd try some paint remover. The more aggressive the better. Try brushing it on, wait a few minutes for it to soften the sealer, agitate with a stiff bristled brush and wipe with rags. Several applications will probably be needed. You may not get 100% of the sealer up, but it shouldn't be nearly as obvious.

"Anyone have recommendations for wet look sealers accessible to homeowners for brick? " ---- Try Behr Wet-Look Sealer... I've used it and it looks fantastic.

Its so pretty with the wash. You could use brick and mortar sealer, water-based, matte finish. Outdoors it will need to be resealed every few years depending on your weather.

Frankly it appears to be too shallow to fill and any filler would stand out. There's an old woodworker trick where one can dab a little water on a hammed ding or use a damp cloth and an iron to steam out dings. There's probably a Youtube video or two on this. Otherwise you could use a bit of the original floor finish and an artist brush and fill it in. That's probably the route I'd take to avoid any unintended consequences. The only other option would be to call a professional furniture touchup person who has a hot wax/shellac iron that can be used to melt a colored filler and lay it in the indentation.