Thank you @AbhaySingh for your response.

Databricks CLI version: Databricks CLI v0.274.0 

I am using a numeric workspace_id, which had worked for the removal of bindings. I tried adding a binding now with string in quotes and received the same errors as before. First without specifying any binding type:

Error: Supported binding types for STORAGE_CREDENTIAL are BINDING_TYPE_READ_WRITE

And second when specifying BINDING_TYPE_READ_WRITE, which is placed within each workspace object, not as a top-level parameter:

Error: assigned workspace 0 does not exist or is not assigned the same metastore as the current workspace