My search-bar-fu is failing me. Does anybody know: can Ello Asty pair with Targeting Astro?

Ello let’s you treat tallon rolls as white. Targeting Astro let’s you acquire a target lock when you execute a red maneuver. Can you use them together on the same maneuver?

my gut tells me no, but I’m curious if there is an official ruling

I’m going with No, as well. Targeting Astro says “after you execute” and Ello is “treat <tallon roles> as white” ... so you are executing a white maneuver.

This is correct. If Ello treats his Tallon Rolls as white, they don't count as red for Targeting Astromech, and there isn't a free Target Lock.

I agree with the No answer. But its not necessarily a completely useless combo (though almost every other droid would be better)

Ello's ability is "may" treat as white. So you could have primed thrusters equipped, perform a T-Roll and keep it red, then acquire the lock and perform a boost via PT. Two "actions" at the cost of a stress token. Its a sort of PTL but leaves your EPT open for something else.

Also, the whole combo still works with the old standard K-Turn so you have the unpredictability of turning around with 1 of 3 maneuvers and can adjust your distance and angle after any of them with the boost.

Didn't this question come up previously and spawn an uber thread where it as a chorus of 'no' against a single 'yes'.... Ah the memories.

The rules are pretty clear here, actually.

Ello Asty "may treat" the Tallon Roll maneuvers as white, so whenever Ello Asty does NOT pick up a stress token after performing one of these T-Rolls, the particular maneuver was performed as a white maneuver, which means there is no trigger for the Targeting Astromech.

If Ello Asty ignores his pilot ability and picks up a stress token after one of the T-Rolls, then the Targeting Astromech triggers and grants a free target lock, because the maneuver has been performed as a red one.

Please keep in mind, that the stress token itself does not really rule things here, it's just a very good indicator if the maneuver has been white (no stress, no free target lock) or red (get stress, get free target lock)