Swiftdata Model crash

I am converting a large core data app to SwiftData and have hit a problem I can't fix, namely code generated by a Model crashing.

Here is the model showing the failing expansion.

Here is the model containing the inverse for the failing attribute:

/Users/writingshedprod/Desktop/Screenshot 2024-05-08 at 20.21.51.png

And here is the mass of core data output generated when the app launches. If anyone can make sense of this I'd be grateful. This is where the problem might lie.

Swiftdata Model crash
 
 
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