Add a second engine on FARA, and you have a Boeing Apache replacement, not a Kiowa replacement (admittedly the original FARA spec is far from a Kiowa).
This will not make Boeing happy. With all the FARA specification changes, Boeing could rightly file a protest to request the FARA competition be reopened.
The Army mandated that FARA must have a single engine, that Army would specif. In fact, it is delays in supplying that engine that has slipped the flight test progrm for FARA. Bell finished its prototype a few months ago, and Sikorsky's I think is now complete or nearly so, but both are awaiting engines.
FARA already is intended to replace part of the Apache fleet.