Chromecast is seen but will not play.

[McFurry]

VLC will not successfully play via Chromecast on my Mac. I go to playback -> renderer -> cast, the screen shrinks down, the pause button becomes a play button, and you can see the name of the video in the media list: but it does not play. To be clear: VLC can see the Chromecast but cannot connect to it. It is not a problem with a black screen with no audio or visual or anything of that nature: it does not connect through.

Important things to know:

1) There are two computers in the house. The other one (also a Mac) runs VLC via Chromecast just fine (i.e. the problem is not with the Chromecast, and I know the steps to put VLC on a Chromecast because I do it successfully all the time on the other computer).
2) I can screen-share my Mac or my browser windows to the Chromecast successfully: it is specifically VLC that does not work.
3) I have tried it with two separate Chromecasts in two separate houses with two separate WiFis: no dice (i.e. its not a problem with my home or my Chromecast.)
4) It does not work with .avi, .mp4, .flac, .mkv,, or .mp3 which feels comprehensive enough to conclude it is not a filetype error.

Solutions tried after looking-up the problem:

1) Preferences -> Reset All
2) Preferences -> Show All -> Reset All
3) Preferences -> Enable/Disable HTTP Web Preferences

I am running Mac OS 10.14.16 (for reasons I cannot update further)
My VLC is Version 3.0.17.3 Vetinari (Intel 64bit)

I produced the following log: https://pastebin.com/wzy7GSVv

Please advise.