Bug discovered by Skywise @ Chaos. Confirmed fix by me editing /resources/entities/pets/cargopet_goliath_beetle.ent . Per Skywise, Ranquathas (player - exact spelling unsure) suggested looking at that, so he actually pointed the right direction.

cargopet_goliath_beetle.ent file is missing this bool:
bool playerSelectable = false

All other pets and cargo disks has this flag.
Since this is missing from the beetle, this is causing odd behavior:

1) The beetle is selectable (in screenshot - no other pet in this game can be selected, nor can any cargo disk)
2) When another player is nearby, his Pet name shows in your target window (Note screenshot, I am standing near a pet named "Testing". My beetle shows the name "Testing" in the target window. Shouldn't be selectable anyways, thus this will fix the issue.