The mother’, father’s too, actually, calls to their family are unlike any sound I have ever heard a cat make. Our second childhood cat had two litters before we got her fixed. She never made any such sound. I will see if I can find similar online. Very well might, u as it was so uniqu, I did not think to look. Food and water had been working well enough.I understand regarding the two dead kittens. You wouldn't have needed their actual moms cry, any mother cat's cry from YouTube videos or similar will likely work, for future if you ever should need to know. I just mentioned it since you were not 100 percent absolutely sure whether you were hearing a kitten amidst all the noise and distractions that day.
She is still stressed on the one hand, trying to understand her surroundings on the other hand, and exhausted. Hang in there with her, be patient and quiet and calm, and move slowly. I believe you know more about all this than you thought