I was able to fix the last problem by creating a new AWS group, adding myself as a user to that group, and giving the group Administration privileges. The AWS interface isn't very intuitive.
However, following the next workflow for a remote batch submit:
env = RemoteBatchSubmissionEnvironment[(*...copied from AWS...*)]
came back with
ServiceConnect::multser: One service was chosen from multiple AWS
services.
and
job = RemoteBatchSubmit[env, 2 + 2]
came back with
ServiceExecute::aws-requesterror: The DescribeJobDefinitions request
failed with the following client error: no AWS credentials could be
found using the specified authentication configuration.
So, it looks like I will need to figure out how to delete multiple services. I'll report back if successful.