Best way to extract values from a dynamo table attribute of a list of dictionaries to use as indexes?

Versions (relevant - OpenSearch/Dashboard/Server OS/Browser):
7.1.0

Describe the issue:
Our table has a attribute, which is a list of objects. Each object (sometimes) has a id : value pair.
objects = [
object 1: {id: 123, other_id: 123455, blah blah other key values we don’t need} ,
object 2: {id: 456, other_id: 1355, blah blah other key values we don’t need} ,
]

Whats the best way to configure our dynamo ingestion pipeline configuration so that we not only index on every other attribute in the row, but also create an additional index on a list of all of the concatenations of “id#other_id”, extracted from each of the objects nested in the list?

I tried dissect, but couldn’t figure it out without many examples – same with my attempt with grok.

Configuration:
using AWS, zero etl pipeline integration with Dynamo for opensearch.

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