Completely? No, you can have it very very consistent if you're cam stalling Freddy. I suppose it's always possible RNG screws you over so hard that there's nothing you can do, but it's definitely not just holding out for good RNG.
Sounds like you might be using the strategy of keeping the right door closed any time Freddy is in the hallway, which is definitely an RNG reliant strategy.
If you are actually doing the cam stalling strategy and still consistently losing, it's execution that's the problem.