Hi Woody,
traffic forwarded by a virtual server to pool members should show up in the pool member statistics.
For non locally attached pool members you have probably a route pointing to the internal firewalls, right?
Do the pool member statistics for the pool_owa show "In" packets but no "Out" packets?
This would be an indicator for asymmetric traffic flow which could be avoided by applying SNAT to the virtual server. It will force all responses back to the BIG-IP and the BIG-IP will return the responses exactly the same way where the requests came in (aka F5 AutoLastHop feature).
Thanks, Stephan