I have a sneaking suspicion that it is the fact that my 2 SQL Servers and the two other nodes that I want to use in this are on different subnets (although I am unsure as to why that would matter).

My boss is going to get me an IP addy this morning, and I'll build a totally separate cluster for these two servers and see what happens.

Trying anything I can think of, this part looks promising to maybe be the issue...

WSREP_SST: [INFO] Removing the sst_in_progress file (20150615 23:31:45.369) 150615 23:31:45 [ERROR] WSREP: Process completed with error: wsrep_sst_xtrabackup --role 'joiner' --address 'x.x.x.x' --auth 'no:no' --datadir '/db/mysql/' --defaults-file '/etc/mysql/my.cnf' --parent '16465': 32 (Broken pipe) 150615 23:31:45 [ERROR] WSREP: Failed to read uuid:seqno from joiner script. 150615 23:31:45 [ERROR] WSREP: SST failed: 32 (Broken pipe) 150615 23:31:45 [ERROR] Aborting