The current version of the aws sdk (v1.x) being used doesn't support multi-region access points (1) Updating to the latest (2.x) is not enough as the logic to capture the bucket and folder path needs to account for the new naming convention allowing for a / in the multi-region access point arn. (2)
AWS has a migration guide for going from v1 to v2 (3)
(1) https://docs.aws.amazon.com/sdkref/latest/guide/feature-s3-mrap.html
(2) https://docs.aws.amazon.com/AmazonS3/latest/userguide/MultiRegionAccessPointRequests.html
(3) https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/migration.html