According to those graphs the lag only occurred for a minute or so at a time then the server was performing fine? This is absolutely not what was happening in the server. The lag would come on and stay on until enough people quit to bring player count down. And I can 100% promise you this was not client side network lag for two reasons: 1.) I am on fios 25/50 and never see even a hint of lag in other servers for hours of gameplay on end and 2.) everyone else in the server was complaining at the same time as me, and several other players agreed that it was only the IBIS combat server where they see this much lag.
I will keep an eye on your server and check back in here next time I play in it to provide more first hand experiences, but something tells me that reporting tool may not be correct, or perhaps it is not tracking the proper metrics to show perceived player lag.