Unable to spot any problems in this project after exporting at default mp4 1080 settings. Do not have VLC here, but playback in Windows 10 media player, Windows Movie and TV player and MPC-BE all were faultless. You might try a different export format to see if VLC likes it better or reinstall that viewer.
As for YouTube, direct upload success can be spotty and often works best in the middle of the night (PST). This is not a fault of VP and the issue is known. The alternative is to export in a YT-approved format and use their uploader.
That said, direct uploads usually succeed here, as did your project... https://www.youtube.com/watch?v=oIJehgCe9qI
The latest release of VP is 8.32, as of this date. Give it a try. For licensed users upgrades are free for up to six months from purchase date. After that, VP will continue to fully function but a fee will be required in order to register the newest. Retain your old install file and registration info.