"Be being" - grammatically correct?

No, “being” in this case is not a gerund because the word in question isn’t behaving at all like a noun. The phrase suggests that something is not being adhered to right now but this non-adherence is not necessarily a property of the thing. It’s like the difference between “you are a jerk” an “you are being a jerk.” The former is absolute and final, but the latter leaves open the possibility that you could stop being a jerk.

There are definitely clearer ways to express this, but I don’t think it is ungrammatical.