Different paths. Our vendor folder on the old laptop, an installed package on the rebuild. I'd compared everything except the imports, apparently.

Keep your working copy. Compare signatures, then recreate it in an isolated environment. That should settle the laptop side.

Too certain. Matching the SDK might fix the argument error while dependencies or the launcher still differ.

You're right; I overstated it. Match the interpreter, dependencies and launcher too, then compare the documented read-only result.

Found it: the rejected argument has a different signature. Both copies are intact, and our working laptop is untouched.

I've narrowed this to different imported SDK copies, but haven't established a supported replacement environment. That's progress, with the rebuild still open.

Different imports are a useful lead. Keeping the rebuild open until the supported environment is established matches what you've found.