Deleting folder with incorrect siteId is a 500 vs. 404 (or 401)

[reganwolfrom]

When attempting to delete from a different site (not default), this request was made:
DELETE /indices/folder/%23my-mail?siteId=default

Instead of returning a 404 (or a 401, which might be more technically correct), it returns a 500.

[mfriesen]

{
"requestId": "IjFuigq_iYcEMGg=",
"ip": "50.71.0.58",
"requestTime": "24/Jul/2023:03:01:35 +0000",
"httpMethod": "DELETE",
"routeKey": "DELETE /indices/{indexType}/{indexKey}",
"pathParameters": {
"indexKey": "#Office",
"indexType": "folder"
},
"protocol": "HTTP/1.1",
"user": "regan@formkiq.com",
"queryParameters": {
"siteId": "default"
}
}

2023-07-24T03:01:36.004Z java.lang.NullPointerException
2023-07-24T03:01:36.004Z at com.formkiq.stacks.dynamodb.FolderIndexProcessorImpl.deleteEmptyDirectory(FolderIndexProcessorImpl.java:207)
2023-07-24T03:01:36.004Z at com.formkiq.stacks.api.handler.IndicesRequestHandler.delete(IndicesRequestHandler.java:79)
2023-07-24T03:01:36.004Z at com.formkiq.aws.services.lambda.AbstractRestApiRequestHandler.callHandlerMethod(AbstractRestApiRequestHandler.java:148)
2023-07-24T03:01:36.004Z at com.formkiq.aws.services.lambda.AbstractRestApiRequestHandler.processRequest(AbstractRestApiRequestHandler.java:436)
2023-07-24T03:01:36.004Z at com.formkiq.aws.services.lambda.AbstractRestApiRequestHandler.processApiGatewayRequest(AbstractRestApiRequestHandler.java:374)
2023-07-24T03:01:36.004Z