It was not to pay furloughed employees, it was to avoid having to furlough or lay off more employees than they did anyway. Furloughed employees did not get paid, but retaining a certain percentage of pre-pandemic headcount was a requirement for the loan to eventually be forgiven.

Source: I was furloughed April 2020 while my employer at the time received over $2m in PPP. Furloughed employees were explicitly told to collect UI.