I'm getting the very same error in my launcher. Has been happening since the 1.19 update.

If it helps, or if anyone is interested, the exact same issue happened to me. However, it lasted several days around the same date and has now stopped. There was nothing I tried that worked. I wasn't willing to go to the lengths that Tony went to (above) but I would have done so if the problem had not resolved itself.
The whole experience smelled a bit like a bug which was quietly fixed in a subsequent update - either to BattelEye or DayZ.

Exactly the same problem except I have less hours than you.
Basically, everything worked forever but in the last 5-7 days, I started getting this error.
What changed??