It would appear that hooktube links are getting caught up in the youtube regex, given how similar they are. I do not know if hooktube and the youtube plugin use similar methods. If you right click on the video and select Copy Video Location on hooktube page, it produces a very similar looking link. It kinda hard to tell as the video links in the kodi logs are very long and critic.

When opening both the example youtube and hooktube links with firefox-send-to-xbmc it appears to play the same video via the kodi youtube plugin. Supported parameters: start, end, loop (1 for on), speed (range: 0.01 to 4), autoplay (0 for off, default is 1). HOW: Just replace the domain in any YT link with and you get a light-weight page that loads YouTube's media files (mp4, webm, etc) directly into your browser's native media player. Bypass country blocks and age restrictions. Share YouTube videos without giving them views. The regex for youtube is picking up hooktube, possibly on accident? The following is the current explanation how hooktube works:

Kodi 17.6 download u tube