just have to stick with SE support.

make all points loud and clear to them. such as a description of what happened followed by

"My isp IS NOT TO BLAME. i am able to log in with another character"
"my network connetion IS NOT TO BLAME"
"my hardware configuration IS NOT TO BLAME"

"YOUR servers have this bug in NOT MY SYSTEM"

basicaly highlight all the points that proove its thier end and tell them that any further implication that your to blame will not be well met.