Still sounds like your reset is firing too quickly. Did you try this as your reset?
WHERE NodeId NOT IN (
SELECT NodeID
FROM F5_Device_V dv
JOIN F5_Pools p ON dv.NodeID = p.NodeID
WHERE dv.F5_Pools_AvailabilityState = 3
)
Still sounds like your reset is firing too quickly. Did you try this as your reset?
WHERE NodeId NOT IN (
SELECT NodeID
FROM F5_Device_V dv
JOIN F5_Pools p ON dv.NodeID = p.NodeID
WHERE dv.F5_Pools_AvailabilityState = 3
)