Clustering and S2S?

Hello,

I am wondering if there is a way to use both S2S and Clustering at the same time. I have 2 servers that I already have running in a cluster that works great. We just opened a new office in another city that is also a new division, so it has it’s own domain.
The 2 that are clustered, are on the same domain, but in 2 different locations connected via VPN. The other office is also tied in to the network via VPN with Forest Trusts established between the domains. I cannot seem to get the 3rd server to connect to the clustered pair. I have all the SRV records added and can ping the domains from each other(domain1 can ping domain2 and the other way around). I try the server to server test, and I get a very long list of connections being established, data being transferred, etc. At the end, it just says The connection could not be established. Though there are no errors in all the other information provided.
One thing that I noticed in those logs is when running the test from one of the servers in the already established cluster, it automatically tries to establish the S2S connection with the other machine in the cluster. Though the IP for that machine is not associated with the other domain at all.

I try telling one of the servers in Domain1(server1 and server2) to test the connection to Domain2(server3). When server1 sends out the ping to domain2, but uses the IP for server2. I have checked the DNS on all servers involved and domain2 has absolutely no records that points to server2. This is really bugging me.

Every article I have found says S2S should be very easy to set up, thus the lack of configuration options in the Admin Console. But I cannot get this to work at all. Clustering was way easier, but I cannot do that with multiple domains. The servers in the cluster have to share a domain and database.

Any ideas what I am missing? I have been through my DNS server settings on all of my DC’s at every site, the SRV records and such are pointing to the correct machines and everything. I am at a total loss.