It works! 
I'm on Windows:
D:\DVR\Imports\Movies\Hallmark Movies Now\The Christmas House 2 - Deck Those Halls (2021).strmlnk
URL in the file:
https://www.hmnow.com/playback/item/MOVINA036532
Channels shows the tag "Hmnow" as the streaming provider in the movie details:
Would it be possible to have a tag that shows "Hallmark Movies Now" or is it too long and you want to keep it short?
On a TiVo Stream 4K, it worked perfectly: it opened the Hallmark Movies Now app and went straight to this movie. When done, I hit the back key 2 times and it brought me back right into Channels. It was seamless. 