Zebra Finch Newborns Left Alone?

I just added two pair of Zebra Finches to my Quail aviary about three months ago. Provided nests, nesting material and food conducive to breeding. One pair started building a nest within a week.

About three weeks in, I noticed one finch was ALWAYS in the nest so I assumed they are sitting on eggs. Based on the date, I figured the babies should hatch about the 20th of November. There was always one or the other finch in the nest at all times. I noticed on the 20th, both were out and every time I came out for the next two days they were always out of the nest.

I finally decided to look inside but it was a straw nest with very small opening (not a wood nest box with lifting lid) so I couldn't see anything. On the 23rd, I decided to put my finger in and I felt flesh with no movement or sounds. I assumed the babies hatched and then died as a result of being abandoned.

I brought the nest into the house and snipped the top half open to see what I could see. There were at least three maybe four babies that appeared dead. When I went to pick one up, it moved slightly and made a small sound. I immediately closed the nest back up, tied it closed and put it back in the aviary in hopes that the parents would go back to the nest. Is it possible or did the parent abandon them and it is just taking a while for them to die?