I was able to fix the issue which was preventing caching. There were 2 issues preventing caching:
The cache was not set to 'Default'. I had previously added my Redis Cache from a region by selecting a region from the dropdown 'Use from' and then selecting the resource from the 'Cache instance' dropdown. The 'Use from' value has to be instead selected as 'Default' and the 'Cache instance' should be kept to 'Custom' value and the connection string has to be manually filled in (of the format "<endpoint-url-of-cache>,password=<access-key>,ssl=True,abortConnect=False" )
The custom url in the backend for embeddings API was missing 'embeddings-deployment/embeddings' in the custom url