My interpretation for the translation of the last panel (last two boxes) would be something like
W... Why'd she lose her cool on that question (ん。。。何でボカしたの)
"Lose her cool" is trying to capture the ボカした (wandered off if in your translation).
She had to stop and think about how to answer the question and it seemed like she went blank for a second, is how I would take it.
Well, I guess asking, as her boss, would be kinda awkward, right (いやまあバイト先の店長って言ってもアレだよね!?)
Or
Asking her about it would be weird, though, since I'm her boss, right!?
Where you could use "awk" for awkward or weird if you want to capture the slang-ish nature of using アレ here.
Currently not in the best state to come up with a better phrasing but hopefully this gives you something to run with.
Edit: Ignore me, Sjiveru below has a better interpretation.