“I do not know the particulars of the situation but have you ever considered having a friend call your daughters references for a “test” call? While unpleasant, it is better than the alternative…”
Just ask a sheilah first as to whether it’s allowed in terms of hilchos loshon hora. I recently read in Sefer Chofetz Chaim that something like that may be assur. (I don’t remember if that was the exact scenario, but I think it was either that or something similar).