Logs Ingestion API / DCR cannot bind custom stream to valid table

We are configuring a custom integration using Microsoft Sentinel's Logs Ingestion API and a custom DCR (test-dcr-shell) in region westus2. We are attempting to bind the stream Custom-ClassificationStream to a custom table CustomClassificationStream_CL, created in the Log Analytics workspace DSPMSentinel.

• The table exists and has tableSubType: DataCollectionRuleBased
• The schema exactly matches the stream definition in the DCR
• The DCR is correctly deployed using az rest --method put
• The DCR stream declaration and data flow routing are valid
• Yet, the PUT fails with:

{

"code": "InvalidOutputTable",

"message": "Table for output stream 'Custom-CyeraClassificationStream' is not available..."

}

This issue persists even after waiting >15 minutes after table creation.

It seems that the validator rejects the DCR due to a missing table, which clearly exists. The result fom the az rest put is as follows:

Bad Request({"error":{"code":"InvalidPayload","message":"Data collection rule is invalid","details":[{"code":"InvalidOutputTable","message":"Table for output stream 'Custom-ClassificationStream' is not available for destination 'la--1249775715'. Please ensure that the table exists in Log Analytics Workspace before creating or updating the rule.","target":"properties.dataFlows[1]"},{"code":"InvalidOutputTable","message":"Custom table for stream 'Custom-ClassificationStream' is not available for destination 'la--1249775715'. Please ensure that the table exists in Log Analytics Workspace before creating or updating the rule.","target":"properties.dataFlows[1]"}]}})

I can confirm that the correct table does exist and Sentinel does show the table and hence should be able to be bound. Any help would be recommended. I am struggling to get these working and keep getting roadblocks.