LTM health monitor logging shows success but all members still marked down

I am trying to setup a new pool for our on-prem BigIPs and apps that routes to a cloud hosted service hosted by a 3rd party vendor and I am having difficulty getting the https based health monitor to mark as up the one IP that the FQDN DNS name resolves to. I've tried FQDN Node and FQDN Node List types for the pool members and saw no difference. The IP resolves fine and auto-populates into the pool as needed. I have a basic HTTP 1.0 get request of type https fetching the WSDL document from the external service. I then enabled "Monitor Logging" on the FQDN pool member that I have in the pool that matches in a simple string I know is in the WSDL. Tailing the health monitor log file in /var/logs/monitors/ I can see it send and I can see the proper wsdl contents and a 200 response code and then it also says '...(_recv_active_service_ping): Response matched regex...' yet the member is still being marked as down. I did a 'tmsh show /pool <poolname>' from the command line and it is showing 1 member but zero available. I am at a loss as to what to try next to get this to work.