We are unable to get authorize.net talking back to CiviCRM in regards to recurring payments.
In talking with authorize.net folks and they pointed out that query strings are not allowed to be used in the Silent Post URL: https://support.authorize.net/s/article/Why-Are-My-SIM-Relay-Response-Transactions-Timing-out-After-Submitting-the-Request
However, CiviCRM docs say for Wordpress you need to use a query string? https://docs.civicrm.org/sysadmin/en/latest/setup/payment-processors/authorize-net/ We've checked the logs and see that authorize.net is not communicating back to CiviCRM. The transaction ID's for recurring payments are missing.
So who is right here and are people successfully using WP and Civi with authorize.net?
We have checked that are servers support connections via TLS 1.2.
On WP 4.9.4 and Civi 4.7.30