Need to get last 7 days of call transcripts, Is stats endpoint the only option?

I have a use case where I need transcripts of calls made in last 7 day. My current approach is to call:

{
"days_ago_end": 7,
"days_ago_start": 0,
"export_type": "records",
"stat_type": "calls",
"timezone": "UTC"
}

and then wait for csv file to get generated. Once file is generated get list of call Ids from file and use the call id in each line of file to pull transcript with below endpoint:

https://dialpad.com/api/v2/transcripts/{call_id}

Two questions:

Is there a more efficient way to pull transcripts directly?
In stats endpoint how can I filter call by USER/GROUP?