Hidden Audio-track inside 264-file

I’m not a codec-newbie, but I’m far from experienced.  

I have several Anran security cameras that record videos in H.264.  My video-editing software (FilmForth) cannot input .264 files so I wish to convert them to AVI/MP4/etc for editing.  But NO converter, apart from the manufacturer’s, has been able to find the audio-track embedded inside and… the manufacturer’s application is “paaainful” to use.

Plus, the manufacturer hasn’t been able to provide details about the codecs/settings that their painful app uses for the audio.  

I have experimented with batch-converters like Prism, HandBrake, VidCoder, and WinX HD.  In each, I have experimented with Dozens of different codecs/settings.  But I have had ZERO success in converting and outputting a file with audio.

REQUEST/PLEADING
I’m attaching two videos (original + the manufacturer’s conversion)…of a cat getting sprayed by a motion-sensing sprinkler (hehe...long story).  From these, can anyone determine how the manufacturer’s app is converting the camera's 264-files and... if so, can you provide steps as to how I might replicate this with other converters?

ATTACHMENT DETAILS
1) Original .264-file from the camera.    [DROPBOX LINK]
    DETAILS
         Video: MPEG4 Video (H264) 1920x1080 12.5fps [V: h264 high L4.0, yuv420p, 1920x1080]
         Audio:  NONE
    NOTES
         -- Sound can be heard when played in the manufacturer’s video-player.
         -- Sound cannot be heard in any other players (Windows Media Player, etc).

2) “Manufacturer-converted” AVI-file.    [DROPBOX LINK]
    DETAILS
         Video: MPEG4 Video (H264) 1920x1080 12.5fps 919kbps [V: h264 high L4.0, yuv420p, 1920x1080, 919 kb/s]
         Audio: aLaw 8000Hz mono 64kbps [A: pcm_alaw, 8000 Hz, 1 channel, s16, 64 kb/s]

3) Log-output from the Codec Tweak Tool for my system.   [DROPBOX LINK]

 
MANY THANKS in advance for any help in this!  
Shout with any questions or if you need further information for this.

Kurt

I can't help you. They obviously use a non-standard method of embedding audio.

Ah, I was afraid of that.

Any idea why someone would use a standard-codec for VIDEO, but... not for Audio?

The cameras are from China. Might they just "happen to be using a code that is semi-standard, there".... but just unpublished outside of China?

DUMB QUESTIONS (warning)
1) Is this strange or... seen fairly often in codec camps?
2) Should I look anywhere else for help or... is this likely a solid dead-end?

Thanks again!!
Kurt

It is common for cheap Chinese cams to to this. Some info here:
https://www.spitzner.org/kkmoon.html
https://code.videolan.org/videolan/vlc/-/issues/22935

Wow (after reading these in detail).  But.. how am I not surprised?

Great links!  There's some details there... and possible solutions which I'll definitely absorb shortly.

Many thanks for all of this!!