Maybe that’s duplicati-ie0ca3083d0d14b738a6889a041d1f582.dindex.zip.aes.
I’m not sure why you call it a parent, but it does reference a missing dblock file, so the
answer being sought is whether it’s an extra dindex or if a still-in-use dblock vanished.
Which system did you ask? This is database-based, so original system may do better
(meaning not give any odd error, if you’re saying you got an odd error after an answer).
Remote missing files but list-broken-files returns 0 points to more info that might apply.