Can TradeZero close out an option position before expiration?

Yes. Accounts which do not have enough equity prior to expiration and exercise or assignment would introduce undo risk should the price change dramatically upon delivery may be closed prior to the close of the options market on expiration day.

If uncollateralized risk far exceeds any in-the money value, determined by risk management specifically at expiration, the position will be closed out prior to the close of the options trading on expiration day.