Fanning out DynamoDB stream into a kinesis stream using a lambda trigger?

Hi, I'm trying to implement a system which essentially provides in-order item-level information about DDB updates to multiple consumers. I'm using DDB streams as Kinesis streams from DDB don't maintain order and deduping (source). However, DDB streams can only have a max. of 2 concurrent consumers before being throttled.

So what I'm trying to do is have the DDB stream trigger a lambda, which serializes the com.amazonaws.services.lambda.runtime.events.DyanmodbEvent.DynamodbStreamRecord, and passes it into a kinesis stream. A few questions:

1. What's the best method of serializing the DynamodbStreamRecord? I've seen some examples using KCL and the RecordAdapter, but that operates on the com.amazonaws.services.dynamodbv2.model.Record object, and not the lambda event objects DynamodbStreamRecord and StreamRecord.
2. When I'm writing code to send data into a kinesis stream, the putRecord API in the kinesis client requires a partition key parameter. If I'm aiming to maintain the same order on an item level in the kinesis stream, should the partition key that I supply for the putRecord call just be the partition key of the relevant item? Thanks!