I think the game engine considers the player-information unnecessary, because you can't see the player and can't interact with him anymore.
Therefore the engine writes the last position in memory and then does nothing with it anymore, until the player reaches a distance at which you could interact with him again.
Then the address will be written again.
Just a thought, idk if it's true.
(I didn't read the source)
Yeah you gotta check the isDormant to make sure theyre actually getting updated. If you get the positions from the radar struct they will always be updated. You can also grab the health from there and it is more accurate than from the player struct.