Oh dear, I see a few problems.
How are you going to balance the thrust with two different sized engines fitted with different gearbox
ratios? different size props perhaps - not good, although you could probably get away with it, what happens when you come to sell. What would a future owner have to say or would they just walk away.
You are also carrying two lots of spares etc, from different sources.
You could spend a lot of money
and end up with a disaster.
However, you have a cat. How about one larger engine
and two hydraulic drives? that would make space for a genny in the empty hull
. You would need to cost it first though.