I'm not finding excuses, I tried to replicate what you said, did not find a problem, then you gave me incorrect information.
You need to share me the file so I can download it.
I tried it and yes, got my ass handed to me, but you neglected to mention they start with a bunch of allies that mobilize for them. I'm going to try moving my army to the west of my country before I DOW. I did manage to find some damaged units on the front line. Told them to repair, they did so just fine, when to a barracks in the next BZ over. In my next test I'll see if I can get them to cross to BZs.
So far I cannot find a case of a unit that does not respond to a repair order. That's the claim I'm trying to prove/disprove.