Salt really shouldn't affect epoxy at all, other than leaving a residue that needs to be cleaned. Most epoxy systems are chemical resistant against much harsher chemicals and solvents than salt or chloride ice melters would be. The salts damages bare concrete because they release heat (exothermic reaction) when contacted with snow or ice. This rapid temperature change on the freezing concrete causes it it
"pop" loose or "spall". This temperature is not great enough to damage epoxy.