I wouldn't trust any kind of clarity enhancement in any gemstone to be stable under any circumstances, no matter what the manufacturer / vendor says.
The problem with doing anything at all to an enhanced stone, even simple cleaning, is that you now own it forever. If there is ever an issue, even five years from now, in the eyes of way too many consumers, it will have been caused by your mishandling and therefore it is your responsibility to repair or replace.
They believe this because the people they bought it from told them that the new treatments are entirely stable under normal care and repair procedures. Given that fact, they couldn't possibly have done anything to damage it, so it's got to be something you did to it. You're the only person other than the lady that wears it that ever touched it, so...
Ask me how I know.