Hi @megz, you are trying to attach an instance profile to a model serving endpoint in a Unity Catalog (UC) shared mode cluster based on the information provided.
However, for security reasons, instance profiles are not supported in UC shared mode clusters. If you want to use an instance profile with a UC cluster, you must switch to Single User or Service principal-enabled clusters. Here is the relevant information from the sources.
With UC Shared mode clusters, we cannot use instance profiles. If you would like to use an instance profile with a UC cluster, you have to either use Single User or Service principal-enabled clusters.
On Shared cluster instances profiles are bypassed because of security reasons.
Please note that the error message you received, "Instance profile config is not supported!" aligns with this information. I hope this answers your question. If you need further assistance, please let me know.
Also, please don't forget to click on the "Accept as Solution" button whenever the information provided helps resolve your question.