A plugin had an unrecoverable error

I tried asking for help and debugging on both the forum and ServerFault, with no success. I am able to make AWS API calls from my server's command line, and I've verified that my aws credentials file allows read access to all users on the system (not that I'm crazy about that, but for debugging purposes I'm doing it).

Version: 5.0.0
Operating System: Ubuntu 14.04
Config File (if you have sensitive info, please remove it):

input {
  cloudwatch {
   metrics => ["CPUUtilization"]
   filters => { "tag:Monitoring" => "Yes" }
   region => "us-east-1"
   namespace => "AWS/EC2"
   aws_credentials_file => "/home/pvencill/.aws/credentials" # this file is currently world-readable
  }
}
output {
  elasticsearch {
    hosts => ["localhost:9200"]
  }
}

Sample Data: ?? not sure what this is; it's whatever your plugin is querying from cloudwatch
Steps to Reproduce: Install the ELK stack, install the plugin, configure credentials, start the service.

Result is regular log entries of the format:

{:timestamp=>"2016-11-02T10:23:24.746000-0400", :message=>"A plugin had an unrecoverable error. Will restart this plugin.\n Plugin: <LogStash::Inputs::CloudWatch metrics=>[\"CPUUtilization\"], filters=>{\"tag:Monitoring\"=>\"Yes\"}, region=>\"us-east-1\", namespace=>\"AWS/EC2\", aws_credentials_file=>\"/home/pvencill/.aws/credentials\", codec=><LogStash::Codecs::Plain charset=>\"UTF-8\">, use_ssl=>true, statistics=>[\"SampleCount\", \"Average\", \"Minimum\", \"Maximum\", \"Sum\"], interval=>900, period=>300, combined=>false>\n Error: No metrics to query", :level=>:error}

I am also facing the same issue when filtering through input cloudwatch .

Here is my Regular Log entries of Format.

[2016-12-02T10:46:21,495][INFO ][logstash.inputs.cloudwatch] Polling CloudWatch API [2016-12-02T10:46:21,496][ERROR][logstash.pipeline ] A plugin had an unrecoverable error. Will restart this plugin. Plugin: <LogStash::Inputs::CloudWatch namespace=>"AWS/EC2", filters=>{"tag:Name"=>"Logstash-NRT-dev-jnb699-IAM-rvm", "instance-id"=>"i-"}, region=>"us-east-1", period=>900, access_key_id=>"**", secret_access_key=>"***", session_token=>"****", id=>"4b8f5f4c9e8bbcbe8424a21513106bbf361bbf7c-1", enable_metric=>true, codec=><LogStash::Codecs::Plain id=>"plain_5d6527b4-bb8d-4e3e-9b37-04d299a7d4db", enable_metric=>true, charset=>"UTF-8">, use_ssl=>true, metrics=>["CPUUtilization", "DiskReadOps", "DiskWriteOps", "NetworkIn", "NetworkOut"], statistics=>["SampleCount", "Average", "Minimum", "Maximum", "Sum"], interval=>900, combined=>false> Error: No metrics to query

logstash-plugins / logstash-input-cloudwatch

A plugin had an unrecoverable error #12