Those two disciplines should be worried because of their scandals, not because of cricket. Boxing and weightlifting are two of the most fundamental Olympic sports, they should only be removed if they are beyond saving at this point, not because they would be replaced by yet another team sport.
Also, I think having both cricket and rugby at the Games is a bad call. This isn't the Commonwealth Games, pick one of the two and leave the other out of the program. Personally I would pick T20 cricket over rugby sevens. T20 isn't that different from "traditional" cricket, while rugby sevens feels like a cheap imitation of the real thing. Rugby sevens shouldn't have been included in the first place, it's pretty much the equivalent of 3x3 basketball, which also shouldn't be part of the program.
So here's my solution: get rid of 3x3 basketball and rugby sevens. And wow, look at that, we just found 352 athlete quotas for T20 cricket this way, which is almost enough for two 12 team tournaments.