I'm kind of surprised that they aren't using the engines and thrust vectoring buckets from the F-22.
It won't fit. The F-15 is made for 118 cm diameter engines; the F-22's F119 engines are 120 cm. 2 cm doesn't sound like a huge difference, but it would require a complete redesign of the engine bays.
The F-15EX *does* use General Electric F110 engines rather than the inferior Pratt & Whitney F100s, which was previously prohibited on the F-15 for political reasons.