I am switching from SIM (and Silent URL) to Accepted Host (and Webhooks), using the Authorize hosted payment page. I do not want to use a payment form on our own domain, if possible.

The Silent URL returned many custom fields about the transaction, but it appears that Webhooks doesn't do this.  The problem discussed here is exactly my problem:  https://community.developer.authorize.net/t5/Integration-and-Testing/quot-Webhook-quot-VS-quot-Silen... But the solution isn't really clear to me. (It was marked 'solved' just based on Brian being available, it seems.)

It sounds like I should use the "transRefId" (or is it "refTransId"?) which I set up, to uniquely identify the transaction, store the details locally in my own db, then when I'm notified via Webhooks that the transaction went thru, use the refId field to locate my db record with the details. Is this right?

Is there really no way to just get the custom fields from the transaction directly?

I'd appreciate some guidance.  Thanks.