There is incorrect logic in data-import-processing with mapping acquisition units for invoices, instead of ids acquisition units names are mapped.
Incorrected mapping occurs in class/method
and as particular example if we in debug mode(Pic. 1) - this method returns "main" instead of "0ebb1f7d-983f-3026-8a4c-5318e0ebc041" from acceptedValues array
Pic 1 - Details view
This incorrect result value causes mod-invoice to fail validation during creating invoices and import fails in general