🙁 Mouse 4 ?

Hi guys. Can someone help me? So i got a working hack, on CS:GO undetected, and at aiming it says:
Aimbot Hold Key = Mouse4

i have an A4Tech gaming mouse but i aint got 4th key... i have mouse1, 2 and the middle wich is 3.
But can i change that button?..

1 thing to note: Middle mouse isn't 3.

Mice that have 4+ buttons are as follows.
Left click(1), right click(2), 2 side buttons being 3 and 4.

If it's already set as an aimbot being "mouse4" and you just do not have a mouse4 button, I just think it's as simple as you can't use it, but I'm no expert.
tl;dr I don't think that there is anyway to change the key to anything else. Sorry