The only option at this point is to install a timer which would keep the keep the gate open during manually set times within the controller unit...we agreed this is not a good option.
After further consideration I realized this 'hold gate open' modification is unlikely to be implemented anytime soon by Liftmaster. So the workaround is open the gate and push the controller reset to disable the timer-to-close. Then cover the obstruction avoidance reflector protecting the driveway with a not-obvious ABS pipe cap to enable the photoelectric safety forcing the gate always open. Now the gate won't close even when driving over the driveway exit loop or pressing the remote. Blocking safeties is generally not a great idea but I don't see any downside risk given a forced obstruction condition in the open position...unless someone is tampering with the system in which case I will be notified via the motion detection camera. This is a manual method but it works reliably and safely to keep the gate always open when desired.