Grenades still don;'t work very well through the forcefield. Assuming you had a job lot of TDs, then they might work better but frnakly you had better hope you are figthing him somewhere unimportant or you might end up doing more damage than he does.
Anyway! You should indeed think about ways to take on the BV-50, but I'd steer clear of trying to 'cheat' as it were, by messing around with your sabres (which you cannot do without new crystals anyway). Instead, you'll have to play smart with him.
Meanwhile, loosk like you guys are out of there- but it is ia Pilot roll to get out of there in time and not be brought down by the explosion...