discovery uniqueness and proxies

I'm in a situation where 2 client have the same range of IP.
I have setup discovery on the deployed proxies, with "Device uniqueness criteria" set to IP address as it the only data I'm sure to get.
Unfortunately the associated hosts are mixed up between the 2 proxies.

I think IP "uniqueness criteria" should include the proxy, or at least give us the option of using the proxy as part of the uniqueness algorithm.