Yep, that is correct. As someone pointed out above, you should be able to renew any existing certificates you have. You may also be interested to read about https://github.com/letsencrypt/boulder/issues/2800, which should decrease the pain in this situation a bit.
If you’re trying to issue for new domains under ortsinfo.at (but not under .kunden.ortsinfo.at) and finding that you can’t, you may want to fill out the rate limit request form at the bottom of https://letsencrypt.org/docs/rate-limits/.
BTW a small note since it’s nonintuitive: wildcards have a special meaning in the public suffix list.
*.kunden.ortsinfo.at in the list means that
a.kunden.ortstinfo.at is a public suffix, and so is
b.kunden.ortstinfo.at, and so on.