To add a few thoughts in addition to @Saalon's answer:
I just think that the implication was that after destroying Rassum's headquarters, the main characters did whatever they could to destroy and hide the dollhouse technology. So that could explain why they didn't pursue mind-wiping defenses.
In addition, it seems that the characters didn't have the capacity to mass manufacture more Dollhouse technology nor did they want to. The shear number of "Butchers" may have been just too many for the characters to feel that making and using disruptors was worth it.
Also, the disruptors may have interfered with how Victor and his cyber-mercenaries function. They constantly uploaded new skills to their brains, so a disruption might have a negative effect on them.