Nothing to do with temperature this m8, how old are your endlers? (the fry that is)
Some endlers dont develop the gonopdium until they are 4-9 weeks old, if your getting lots of females and hardly any males, then thats just unlucky.
Maybe when the others grow more and start having fry, they will be diffrent have have more males.
I can 100% tell you the temperature has nothing to do with it.
I have my endlers at 28 degrees, drop it to 26 degrees every month for 3 days , this way you get a good consistency of breeding patterns.
Mine at mo are dropping every 17-20 days. The large female i have every 17 days and is unbelievably consistant.