I have that same problem with bookings ex Indonesia. I want Q class but the site often only offers V or W. So far i always managed to work around this by using one of two strategies:
- play around with flight dates until i find a combination where V/W are sold out and therefore Q class is offered
- use a return date > 3 months from departure. V/W usually have a max. 3 month validity and for longer trips Q is offered.
Once i have this ticket issued in Q class (but on wrong dates) i just call or mail TG and ask them to rebook to my desired dates.
It's a bit silly but works. I don't mind making a call to them, for me the most important is that i can avoid the trip to the TG office (which would be required if booking with the office because they can't accept card details over the phone).