The worst part of Trump’s endgame is the pressure on Republicans in the states either not to certify results or to appoint electors in defiance of the results. It’s one thing to delegitimize the election (both sides do this, although Trump is in a class all of his own) or file serial lawsuits that repeatedly collapse of their own implausibility, but to try to overturn the results through brute political force, after having failed to establish widespread fraud, is quite another. Republican officials in Arizona and Georgia have so far held fast under the pressure and deserve great credit.
Meanwhile, dozens of Pennsylvania legislators have called on Congress to reject the state’s Biden electors. This isn’t going to happen because it’s necessary to get both houses of Congress to uphold an objection to electors, and I doubt either House would. Even if there weren’t electors from Pennsylvania, Biden would still handily win the Electoral College.
(The scenario where you could get a breakdown of the process and enter uncharted territory would be if there were rival slates of electors from a state and the two houses of Congress split over which to accept.)