I bet he'll insist on a voice translator for his debate. Oz should start practicing now how he can talk fast or slightly mumbled so the machine won't translate correctly. Then destroy him in the debates and that will seal the deal.
Impaired vocal or physical skills after a stroke aren't uncommon. It would be Fetterman's cognitive skills that would make the difference so instead of making an issue of Fetterman's vocal skills Oz should concentrate on his responses and come up with coherent answers to those. If he can.