Jay had an epiphany.
It was when they started to change. Their goals at first was to free themselves against their oppressors and live quietly, but they demanded more. They wanted to establish their own empire. He obliged to their demands, for the time being.
Jay knew the risks very well. He had to carefully consider the consequence and what transpired at the end of all of their efforts were misgivings of their desires. They became greedy, arrogant, tainted darkly by their ambitions.
When the council found out about their existence, everything became hostile. His vision clouded by the likeliness that they will knew where were they and what they’re up to. So, he had to kill them. In spite of that, the members of Ordinus remained intact of their ill intentions and continued to exploit other people into their experiments and them as a merchandise.