GTM not seeing Virtual Server

I came across the following excerpt while reading Deb's "GTM, know thyself" article, your problem may be related.

 

 

It is possible to use the GTM management IP address when defining the IP addresses for the server address list. For remote device monitoring to succeed, however, you must use the GTM Self IP addresses, not management IP addresses. If you configure the GTM object using the management IP addresses instead, GTM will not be able to monitor virtual servers and other remote objects, and will mark all objects red/unavailable.