How to map Dynamics Multi Select Option Set in Synapse Activity

Question

I'm trying to map a value from a Datalake table to a Dynamics Multi Select Option Set field in a Synapse Pipeline Activity

I have 2 fields, 1 is an Option Set which works: vel_frequency,

 "source": {"name": "vel_frequency","type": "String"},
 "sink": {"name": "vel_frequency","type": "Int32"

the other is a Multi Select Option Set: vel_program

 "source": {"name": "vel_program","type": "String"},
 "sink": {"name": "vel_program","type": "String"

I've tried various mapping type values: Int32, String... This is the error message, despite the type set to String: error: error message: Incorrect attribute value type System.Int32

This is the data preview to show the source data and the Dynamics column data types

There is a page that states there are known limitations with Dynamics Multi Select Option Sets: You can import multi-select field values to existing records, but you can’t import them for new records.

Any ideas of any work arounds to achieve this mapping in Synapse?