CSharp SDK validation fails with a bug

[davengt17]

Describe the issue or request
I'm currently trying to merge a PR which updates the typespec data model for my service: https://github.com/Azure/azure-rest-api-specs-pr/pull/23844

However, it fails in the csharp & python sdk validation, and the error for csharp is shown in this link:
https://dev.azure.com/azure-sdk/internal/_build/results?buildId=5180632&view=logs&j=83516c17-6666-5250-abde-63983ce72a49&t=00be4b52-4a63-5865-8e02-c61723ad0692

The error looks like an issue from server side, with namespace.split not a valid function. Please look into this issue

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how these changes might work for multiple services.

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[live1206]

.NET SDK validation is optional for spec PR merge, you need to fix the failure for python, which is required