hey lonedog,
can you check something on your BB?
Open your calendar and go to calendar options form the menu. Under 'Calendars', select your gmail calendar that is syncing ok and tell me if the option 'Wireless Syncronization: ' is set to Yes.
Mine is set to "No" and is not changeable
Might be time for a wipe of the BB to get rid of several years worth of OS upgrade baggage.