The foundation for a 5.7 Swap

So was it a Megasquirt issue? Were they running megasquirt 3x? Should I be concerned?

No, cuz guys like that have more money then sense. They broke 4 motors with all different systems. It was a user error I'm sure, not an efi issue. Ms is proven over and over again to be reliable. They only upgraded and enhanced its base design for better quality and performance, and options.