Hopeful NAT Fix! No loopback!
MASSIVE thanks to @RandomSolution#6158 !!!

Download this zip file and replace authserver.exe and dbserver.exe in your server's bin directory with the dbserver.exe in this zip. Maybe back up your dbserver.exe first!
Torrent links:
magnet:?xt=urn:btih:BE2D888C9F6B6B19A13780B265FC556EE59769C1&dn=dbserver-nat-fix.zip&tr=udp%3a%2f%2ftracker.opentrackr.org%3a1337%2fannounce&tr=udp%3a%2f%2ftracker.openbittorrent.com%3a80%2fannounce
magnet:?xt=urn:btih:C5D7542B4A3CC0EC8F8D7DAB028E67608F8A36F3&dn=patched-authserver.7z

Disable any loopback adapters you may have installed.
Next, copy the lines below, edit in your IP information, and paste them into the servers.cfg file:

// First RouteIP is External WAN IP
RouteIp 123.123.123.123
// All following lines are optional!
// Second RouteIP is Internal LAN IP
RouteIp 10.1.0.2
// Any RouteIp lines after this point will send the LAN IP to clients
// who connect from an IP matching the first two digits.
// ie "RouteIp 10.2.0.0" would match 10.2.0.10 or 10.2.1.30 etc
// The Internal LAN IP above does this automatically for that IP.
RouteIp 10.2.0.0
// Also optional, if you wish to use the IPs from the cohauth database, uncomment the line below.
// The database IPs will only be used for routing clients to the dbserver!
//AuthDBIP 1