How to load multiple invoice numbers via Mass Additions FBDI

Summary:

In the "Invoice Number" column in the FA Mass Additions FBDI, client has attached multiple invoice numbers relating to a single asset. For example for Asset A, the invoice number column is populated as INV1234567, INV3455424, INV87437183, INV72348749, INV23341131, all invoices separated by a coma. Since the total length of this is exceeding character limit of 50, the load is erroring out. The system is viewing this as a concatenated single string of text > 50 characters.

Is there a way we can bring in all invoice numbers? We tried to use a DFF, but apparently there is a character limit for DFF and some invoice strings go beyond 1000 characters as well.