See, this is one of those times when, as a GM, I’d let coolness trump RAW in a hot second.
Player: Nice. I duck under the ghoul’s claws and then, while he’s overbalanced, trigger my force rings, sending him sailing into the other ship. Can I use riposte for that?
Me: Why not. Awesome. How much damage? Okay, you shatter most of his bigger bones. His broken corpse sinks beneath the waters, leaving nothing but a greasy splotch to mark his passing. Now…
That said I get that you’re handing the PC a bigger advantage than Riposte is supposed to confer, so I probably wouldn’t make a habit of it.