Sorry to hear you have a bully, I had one in my last hatch as well. If was me I probably wouldn't open it because it can cause shrink wrapping. What I did with mine was as long as it was dark in the bator the bully would rest. I cut out 2 pieces of cardboard to cover the viewing windows and...
Hopefully you will get home to some action, but don't start worrying too much if you noticed they were a little behind on day 18. Keeping my fingers crossed for you