PHI have the Real source file for ant-man quantumania, so apparently the reason why the 4.5gb ones and all other encoded from it has Audio taken from Cinema is because the OG leak is came from Russia and language spoken is russian. So they encoded it or mux with an Eng audio then leak them outside Russia.
From the russian leak i can notice the difference as the background audio is a real "WEB" quality same as the video as it is real "WEB" quality too, and only the voices are Dubbed.
OG File is 4.9gb (Strip the OG AAC audio with russian dubbing and mux cinema audio hence became 4.5gb)
- Endgamer