As of 2021, after the rework in Cube (with the Wizard, and magic wand, and stuff), use DEFEATED_PLAYER instead of DEATH_PLAYER. SPAWN_PLAYER still works. As mentioned, you can use these two events to trigger the states, just by dragging the states to the Event Editor of each event (as if the states were Sound SFX's) and then follow the remainder of the lesson normally.
You can check event names, states, switches, and other stuff from the Cube demo via the Wwise_IDs.h file. However, bear in mind that there might be some events declared there but not called in-game, meaning some stuff there might not work at all (like the PLAYERLIFE state). Anyways, the folder is C:\Program Files (x86)\Audiokinetic\Wwise 2021.1.2.7629\Cube\cube_source\src
Lastly, AudioKinetic will release the revised version of their Wwise2021 tutorial in July, so don't worry too much about all this right now.