My question involves divorce in the State of: Ohio

In my case, defendent was living abroad at the time of divorce filing, and complaint was personally served by government lawyer (public prosecuter) oversea. Proof of service for initial complaint and summons are foolproof, and cannot (at least should not) be contested in the future.

Defendent failed to answer the complaint, and default divorce judgement was entered. It was a simple divorce, with no kids or money involved (I was student, hence no money at the time). This was about 6 months ago.

Looking at court's website, "final appealable order" was mailed by the court to defendent soon after the decree was granted. I did also provide a copy of divorce decree but it was hand delivered, hence no proof exists.
1) Is this a problem that I don't have proof of service for the final jugement? 2) What could she do in the future if she wants to open this case again for some reason?
3) Could she claim that she didn't receive copy of order, hence could not appeal before, but she wants to appeal years later because she "just" found out?
4) Could she just nullify the judgement all together because she "didn't receive" copy of judgement (even though she did)?
5) Is there any remedy now? Could I mail a copy of judgement via certified mail now?