I have mobs that are spawned in a ticking area that is far away from my current position. When I teleport them to me using commands, they are successfully moved but fail to render. I can tell that the mobs are still near me using the /testfor command. This happens with all types of mobs that I have tested.

The mobs still retain some functionality when teleported. Tamed mobs, for instance, still follow the player even if they are not visible. This is not true for all functions, however. I have a custom mob that can be interacted with by right clicking on normal occasions. This function no longer works after this teleportation issue occurs.