I practiced this strategy with 0/0/0/20 in multiple runs and while it does kinda work (it more or less guarantees that you will finish 0/0/0/20 run, the game depends so much on RNG that you’re still pretty much fucked. I only managed to get 2 foxy raids in one run, in all other runs I got 3 hits which result in getting either like 1% or 0 power near the end and barely making it out only thanks to freddy’s sequence taking like good 20 seconds of 8:35 night.
I can’t imagine how one could beat 4/20 without extreme luck with Foxy RNG. Sounds like pure statistics and necessity to do bilion runs.
Also I compared it to few original FNAF 20/20/20/20 runs I found and it seems that Foxy here is still more buff than in regular FNAF.