Raise Dead programming/macro help CLASSIC Wrath

Developing an AddOn. Lets say I have a Death Knight from level 56 onwards. So Raise Dead is known. No glyph.

I’d like to test for Raise Dead being “available” - i.e. there’s a nearby corpse so a button press and I’m good to go. If no corpse, and no dust, then waste of time trying to click the button.

It’s easy to test for dust. But in the abscence of dust I nead a viable corpse nearby.

There must be some API call which will return a result along the lines of “can be cast” or “go get yourself a corpse/dust” lol.

Any suggestions no matter how wrong are much appreciated as it might be a useful lead anyway. I’ve pretty much checked all the spell related API calls I can think of.

I just know I’ve missed the bleeding obvious somewhere!