Not many dictionaries list freefall as a single word. The Macquarie is one that does. And it's used frequently - from what I can see, more often than free-fall and almost as much as free fall.
A very recent example, from Forbes on the 11th of this month: "The last time stocks went into a Covid-crash-like freefall was in September of 2008." And on the same date the word was written that way by the Boston Review, University Times (Ireland) and on the website of US TV channel WMUR. All these examples were using the word in a figurative sense - not writing about a physical object subject only to the force of gravity.
I'll add freefall, but bearing in mind its absence from most dictionaries, and players' likely uncertainty about how this expression is written, it will be rare.