Is any of FIPS about ensuring interoperability?

Yeah, there's a ton of correctness testing involved. That's mostly at the algorithm, rather than the module level, so it'll fall under CAVP/ACVP rather than CMVP.

	▲	akerl_ 4 hours ago \| parent [-]
		That's not for interop, that's for "are you actually doing the crypto you said you'd do". It's designed to prevent broken crypto, not to ensure coordination between parties.