LOL...I am not sure why people make such a big deal about cutting open eggs, sure they are able to do it themselves, and the argument that they do it in nature...well, Yeah..they do...but this is not nature...
We put these animals in boxes, feed them more than they probably would feed on in the wild, the eggs are most of the time incubated artificially....why would cutting the eggs open be any different... everything else is not natural...,.
Honestly, I would cut them open, as long as your careful, there should be no problem at all, I have seen a few videos of breeders just taking a razor blade, and slicen and dicen...I guess when you've done it hundreds of times...it gets to be quick...but yikes..lol I wouldn't go all suishi on the eggs, but a little cut to open the egg up is not going to hurt anything in my opinion...
I see nothing wrong with carefully cutting them open...I personally wait till I see little "Scratches" like they are going to start to cut threw on thier own, but havn't yet...but if its been that long...I would think it would be ok...
don't some people say after 55 days its cool to cut?....
Let us know what happens either way...GOOD LUCK 
Last season I cut open our Jungle Carpet Python eggs, and it was just fine...

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Executive Reptiles
Amanda Kingsbury & David Kendrick
www.executivereptiles.com