Possibly, but it popped the top open. Maybe it's possible to do that by just flexing some muscles.

While an egg or cocoon might be airtight, it must also still remain air permeable. Everything must be able to breathe. So while there might not be a visible flow of air, like through an open window, oxygen and CO2 still make their way in and out all the time.

Also initially the insect might break the egg/cocoon open without extra air, just by simple mechanics, but once it's out it starts to pump air into itself.