I'm curious (and am also obviously not Togoalandbeyond.)

Did the water accumulate in the pan after fridging? The reason I ask is that apparently some custard pie fillings have a tendency to "weep" if they're overbaked and refrigerated. I've even had this happen with pumpkin pies I've purchased from the bakery. According to what I've read, using a bit of cornstarch or flour in the mixture lessons the filling's sensitivity to overbaking, but since we aren't allowed either of these products, I can only suggest that
maybe it was in the oven a tad too long..?