I am pretty sure that TW server is the only one seperate from JP GLOBAL NA and SEA..
Global+NA+SEA+JP+KR has same sever,TW+HK has other one
hope Yaskashije can help
For me i only use defense multiplier to 2 or 3 on pve, dont use it on tribe tower, lost sector, interception, and simulation where there is ranking system they can detect your stats.