AWS Config PutConformancePack -- 500 InternalFailure error, null error message

I have been working with AWS config for conformance pack compliance and as of today it is no longer allowing me to deploy a conformance pack via an s3 template upload. The error occurs only when deploying via s3 template, using a sample pack is fine.

I have been using the same s3 bucket and IAM user for some time to perform these tasks and have not changed anything regarding permissions. Config has read access to the bucket and the bucket policy I am using is the one noted in the docs for allowing Config access, I am deploying in the same region as the bucket (us-east-1), and the IAM user account I am using in the code has the relevant permissions outlined in the docs. I have even tried making the bucket completely public but still no dice.

The failure is happening both via the AWS Java SDKv2 and in the portal.

Error Message:

null (Service: AmazonConfig; Status Code: 500; Error Code: InternalFailure; Request ID: d116e7a3-c268-423c-a28a-8f2802e92125; Proxy: null)

Java Error:

null (Service: Config, Status Code: 500, Request ID: e7174ac8-cfae-49b4-a64c-08667f2db10b, Extended Request ID: null) software.amazon.awssdk.services.config.model.ConfigException: null (Service: Config, Status Code: 500, Request ID: e7174ac8-cfae-49b4-a64c-08667f2db10b, Extended Request ID: null)

Dev Console Message:

{"payload":null,"message":"null (Service: AmazonConfig; Status Code: 500; Error Code: InternalFailure; Request ID: d116e7a3-c268-423c-a28a-8f2802e92125; Proxy: null)","errorCode":"InternalFailure","statusCode":"STARLING_FAILED"}

The lack of description is not giving me much to go off of, this error is not listed in the AWS docs for putConformancePack anywhere beyond this section in the "common issues" for Config:

InternalFailure The request processing has failed because of an unknown error, exception or failure. HTTP Status Code: 500

There is a CloudTrail configured and it is logging Config events but no events are registering when uploading via s3 uri, the events only appear when deploying using Sample Templates. Has anyone seen this/have any ideas on how to debug it?