I've said it before and I will say it again, people. Try listening this time.
Protein in and of itself elicits an insulin reaction. Whey is a very quickly-digested protein. This means that it can result in a rapid secretion of insulin. Though the amounts may not be too high, the speed of the reaction itself can be enough to kick you out of ketosis. Same thing with glutamine. So? The insulin secretion is not carb-related. It will be cleared rapidly, and you will be back in keto in no time.
Besides, any possible snag that you might have with G-Plenish is by far outweighted by the immense amount and intensity of the benefits it provides.