Here is what we know about that, (Maybe). The lectern is still suspect I would think.
"Most importantly, everyone permitted inside the debate hall tested negative for COVID-19 prior to entry. Individuals traveling with both candidates, including the candidates themselves, had been tested and tested negative by their respective campaigns."
Based on everything we know about this coronavirus there's no way Trump could have been infected on Tuesday and progressed to the point he needed oxygen and hospitalization by Friday.
The timeline makes no sense.