I asked Jesse Sky (Lead Flashpoints and Operations Designer) what might be going on here. He mentioned that this may be an artifact of how tab targeting prioritizes enemies, and that it might be helpful to change your keybinding to "target nearest enemy." Let us know if this helps!
It's more of an issue that the probes at first are not considered an enemy but as a neutral mob (thus the yellow nameplate). They can be tab targeted easily once they are hit by someone (forcing them to have the red nameplate) but the issue is getting the first hit off.
I don't believe it is possible to tab to a neutral target as long as they are considered not a threat.