That’s not the problem. He can look at web sites and he doesn’t hear unknown. The ;problem, as I discussed in a previous message, is leaving browse mode on.And you may be right. But he reports it saying "pane" when he expects it to read something. That is one of the symptoms of COM DLL deregistration.
It may be an outlier in this case, but on the other hand it won't hurt him to try it either.
As an aside: running Edge 90.0.818.62 here, and neither in browse mode or focus mode, do I get the speech output he describes.
"Beware of wishing for justice... You might get it." - Lois McMaster Bujold