Yellow-shell on Overdue duck egg day 30, still alive no internal pip

[Animal Export]

Hi So this duck egg is overdue and still alive. yesterday I mistakenly thought it had pipped internally so I decided to assist. When I opened it up, the membrane was still intact so I followed a suggestion to place clear tape over the hole. the bottom of the taped egg’s shell is turning yellow, could this be bacterial? the bird inside is still alive but separated from the other eggs.

on the bottom of the aircell on the inside it looks like the membrane is growing up on the shell or maybe the yolk is leaking??? the duckling is still moving but I don't know if he'll make it...

It might not make it because i popped an egg and it did not make it!
But did yours make it?