Pressure will mount if the other 3 commit to playing while the BIG and PAC are standing on the outside and wondering about their decision. I have to believe this scenario was discussed among members and most likely they have an answer when and if this occurs. However if the pressure is sufficient, the decision could be reversed if conference members can tolerate the risks of injuries and illnesses  due to covid-19 and litigation liability. Risk is immense and lawsuits likely if a university is at fault. JMHO.