I’m glad to hear you worked around it .
For what it’s worth, parent subobjects ending up on the derived asset as a bug isn’t completely unheard of. Inheritance of properties, including UPROPERTY references to subobjects, work by first inheriting from parent to child: first inheritance is applied to the child, then overrides restored. If overrides fail to restore, data loss occurs.
Since the problem is related to cook determinism, this bug and this fix might be relevant. Either way, glad to hear you’re unblocked.
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