I had that in my VT, pretty sure it was something in the trans itself, it happened after someone took my trans cooler out and didn't tell me so all my trans fluid came out lol. Kind of hard to tell exactly from the video but it sounds very similar. I drove with it for 6 months with no problems, then car got stolen so don't know how much longer it was gonna last
Some of the idler pulleys have bearings in them. I couldn't pin point it myself so i took it to my mehcanic who fixed it. One pulley was a straight replace and i'm pretty sure one or two have bearings. I also got the harmonic balancer replaced at the same time. Not a peep since.