ok, if I were in your shoes, I'd tell my HR folks what happened -- because "losing coverage" under different circumstances is a qualifying event. just don't know if "this" circumstance is one of those that are defined.
Like if I were to get divorced and lose insurance, I could enroll outside the open window.
Oh -- and some other thoughts come to mind.
Who is court ordered to provide insurance?
And from this point until insurance is reinstated, I'd insist that everything gets processed under insurance first (which there is none), and that the balance left is on the parent who is supposed to carry insurance.
And if you end up picking up the child on your insurance, file to have CS adjusted to reflect that.
You might even wanna file now to have that part of the decree updated and amended -- look at your CS calculation sheet and see how insurance is handled by your state.