Hasn't happened on our Rolf Tandem wheels. But it's happened to several Zipp aluminum freehubs on my single bikes.
It's usually not a big issue. As you've found it can make cassette removal a little more difficult (pushing at the base of the cog with a screwdriver helps)
Worse case, it pulls all the way through the spline, and you have to get a new freehub body. But unless it gets to that point or is causing the cogs to move around, just ride it untill it wears out.
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You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.