100% Support.
For starters, w/o this, there's pretty much no incentive to complete the fally achievement diaries, aside from monkey/achievement cape.
Secondly, the mole locator doesn't make killing the boss take any easier mechanically (given that it's pretty braindead to begin with) it just makes it take less time.
And lastly, in this wouldn't be overpowered, as even with the mole locator, on average, mole would still be a slower method to get nests than Callisto.