Sorry it took me to get back around to you. I downloaded your slice, and ran it. When playing your slice, it also buffered just as before. I am including the logs here.
I did a test. If I play both files (your slice of 1917 and my copy of 1917 that I purchases, in Google Chrome, they both play fine. However, if I play them on the Desktop App they buffer. I didn’t try them on the Samsung TV. The Desktop App buffering your slice is what I logged. I also tried playing them in VLC directly pulling from the NAS. Both seemed to play/stream fine with no issues.