GTM iRule Help?

This says that you can use the LB::status command: https://clouddocs.f5.com/api/irules/GTM.html

If this were me, i'd start by using logs to check everything before putting them together. And maybe define exactly what you want it to do - write some pseudocode first. And support are right - this is more like a PS engagement. PS has many ways of doing engagements, partly based on where you are. Often we will charge on an hourly basis so it might be worth looking into.