Egg developing slow

[StickInsect123]

Hi, I am incubating four eggs in my incubator, and 3 of them are doing great but 1 seems to be developing but a lot slower than the others. So there is a chick inside and it’s day 18 but it is way behind as if it’s been in there for a week only. Should I leave it in? Will it explode?
The two pictures with the lighter egg is the one that isn’t developing properly and the picture with the black egg is a good one for reference.
Thanks in advance!

 

[Cheekychook12]

Hi, I am incubating four eggs in my incubator, and 3 of them are doing great but 1 seems to be developing but a lot slower than the others. So there is a chick inside and it’s day 18 but it is way behind as if it’s been in there for a week only. Should I leave it in? Will it explode?
The two pictures with the lighter egg is the one that isn’t developing properly and the picture with the black egg is a good one for reference.
Thanks in advance!

Personally I can’t see anything developing in the clear looking egg, no veins and nowhere near developed enough for day 18

 

[LaFleche]

All I see is just a big egg yolk in the first picture, no veins or any kind of development.