There seems to be a

Test(uint id,string debugName,BaseEntity ent, BasePlayer player, float maximumDistance)

 now that handles most things, making the "OnVisibilityCheck" hook not work anymore (for some usecases).
Could you please move the hook into that Method? It also gets called by the current location, so it should work for all cases.

Unfortunately I am not familiar enough with this stuff (yet), to send a PR on github. :(