FWIW: There were a number of Video9/Hi8 camcorders in the UC series. The UC8 featured stereo audio and an external mic jack as well as the internal mic. If something was plugged into the mic jack the internal mic was disabled.

Video8/Hi8 stereo recordings used a L+R, L-R, recording scheme; mono camcorders could play back the recording in mono.

If a balanced mono external mic was connected via simple adapters to the external mic jack one could get left and right channels recorded at equal level but out of phase. Playback on a mono camcorder would have essentially no sound. Playback on a stereo camcorder would have left and right channels out of phase. A stereo copy to a stereo VHS would have out of phase left and right HiFi channel - and an essentially silent linear track on VHS VCRS with a mono linear track.

A sample of the same scenes from the VHS copy would be interesting.