Ossia with beam too long

[Knute Snortum]

I'm having a problem with the ossia of a fairly convoluted two
measures (because Chopin played fast and loose with the rhythm).  The
broken beam extends a little too far into the next measure.

I've attached a picture of the ossia as I want it, with context (I
don't care about the dashed lines), the ossia as I have it now, a MWE
that produces that ossia, and a not-minimal example that provides
context for why the measure is written so strangely.

Any help would be greatly appreciated.

--
Knute Snortum

ossia-desired.png
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ossia-problem.png
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ossia-context.ly
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ossia-stand-alone.ly
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