Chrome flag on Android: --use-file-for-fake-video-capture not working

I wanted to inject a video into the WebRTC getUserMedia() in an Android device running Chrome. But the flag --use-file-for-fake-video-capture is not working (WebRTC is giving a NotFoundError) even though the path seems to be valid.

What I did:

1. Enabled the flag "Enable command line on non-rooted devices" in chrome://flags
2. Added the below flags to /data/local/tmp/chrome-command-line

_
--use-fake-device-for-media-stream
--use-fake-ui-for-media-stream
--use-file-for-fake-video-capture=/sdcard/example.y4m

('_' is required for the flags to work)

3. I also tried omitting permutations of the above flags. Didn't work. --use-fake-device-for-media-stream and --use-fake-ui-for-media-stream alone work perfectly.
4. I tried changing path from /sdcard/example.y4m to /storage/emulated/0/example.y4m. Didn't work
5. The file example.y4m is working fine since I tested the same flags on Chrome running on my Mac.
6. I verified that the flags are being enabled in chrome://version

Device Info: Pixel 5, Rooted & bootloader unlocked