Ban for Cheat/bot, support say: the ban was correct and not negotiable, everything will remain as it is.
Support is just some guys trying to do their job. This is no different than what most people say they heard from support, when they first contacted support on their own. It's not just WoW either, when I got banned from RIFT, that is what Trion's support originally said to me as well, before I escalated to a more senior GM that reversed the ban.
We don't know what you said to them that they responded this way to, we can't verify that you used nothing but ISBoxer (this would even include things you may have stopped using weeks ago), we can't determine that you didn't set up some macros in your mouse software, etc.
With that said, if all you want is keyboard and mouse repeat, what you want to do is use the Quick Setup Wizard, and when it asks a configuration style, choose "Generic Broadcasting" instead of "MMO - Standard".
But again, there are thousands of multiboxers in US, EU and other regions, and these features of ISBoxer are 10 years old -- and in ubiquitous use by WoW multiboxers.
There's people streaming WoW multiboxing on Twitch constantly, including in EU, and I guarantee they are all using these features that you're asking how to disable. Some of them have even been banned based on player reports -- we've talked to multiple streamers in the last year who had gotten banned, and then got the bans reversed. At least one of those was an EU player!
So again... it really depends on what you're doing while you play... I still recommend reading the linked threads.