Washing machine shaking

Likely a failed transmission (I was going to go with bearing before I heard the video) and likely costs more to fix than getting a new washer (almost certainly costs more to fix than getting a clean, working used washer.) But, if you like to look, look up the "tricks" to getting into your model of washer (the last one I tore down had "places you shoved a putty-knife" that unlatched the cover) - there's usually something non-obvious like that, but the internet has largely circumvented these "trade secrets of the appliance repair trade" if you look hard enough.

It's also helpful to look for "common problems" or just problems and your model number.

I'm not familiar with your orbital transmission. But, what brief research I did implies the transmission is a common replacement on these, at almost $300. So, get a new washer.

A simple test on yours was to see if you could spin the big pulley by hand. It would turn only if still "good". The motor is trying to spin the transmission but it's completely locked up. But, if you can wiggle it, beat it with a sledge hammer or ask it nicely to move then move it & try an agitation run to see if it engages. If so, then still get a new washer.