My goodness..you guys have/are going through a rough time. I hope things turn out well with these two females for you. Keeping my fingers crossed for these 2 and I am so sorry for your loss.
The male would have nothing to do with it. A couple factors that do guide females towards prolapse is too small/young to be bred and an out of shape females. People always say go by the rule of '3', 3 yrs old, 3 foot long and 300 grams. What tends to be left out is just because a female is 500 grams doesn't mean she's fit to breed. If they don't have good/great muscle tone, they are more prone to prolapse. This is also a big cause of egg binding. I'm sure in some cases maybe stress of cohabbing gravid females might cause prolapse and egg binding too. I'm not saying any of this is the your case, just this is the general causes of these problems.