A good quality ATF doesn't need any additives.
Lubegard is an excellent ATF additive.
If their bulk fluid REQUIRES Lubegard, maybe you should find another shop. Or, buy your own ATF, bring it with you, watch them load the flush machine, and watch them flush your vehicle with it.
For your vehicle, ANY synthetic Dex/Merc, ANY DexronVI, and ANY MerconV would work perfectly WITHOUT any additives.