Hi,
If you are unable to turn the engine at the crankshaft, it does sound as if it is locked. Also, listening to the video, it seems something may have come apart internally.
Do me a favor. Remove the upper timing belt cover and see if the belt is still attached or if it is broken. (See pics 1 and 2) The good thing is this is not an interference engine, but something is happening.
Also, it is possible that a head gasket has failed and allowed coolant to fill one of the cylinders. To check for that as a possible cause, remove all the spark plugs and see if the engine will turn then. If you do this, stand back when doing it because if one or more is full of coolant, you will be covered.
Let me know.
Joe
See pics below.
Images (Click to make bigger)
Wednesday, March 1st, 2023 AT 6:43 PM