AWS javascript SDK SES SendMail Illegal Address

I'm attempting to send mail using AWS SES.

Here's the error I'm seeing:

{
    "message": "Illegal address",
    "code": "InvalidParameterValue",
    "time": "2017-06-02T03:12:37.110Z",
    "requestId": "544c6aee-4741-11e7-9cf5-a709f069aa99",
    "statusCode": 400,
    "retryable": false,
    "retryDelay": 73.04001529701054
}

Here's the request object being passed in to SendMail method of AWS.SES for javascript SDK.

{
    "Destination": {
        "BccAddresses": [],
        "CcAddresses": [],
        "ToAddresses": [
            "success@simulator.amazonses.com"
        ]
    },
    "Message": {
        "Body": {
            "Html": {
                "Charset": "UTF-8",
                "Data": "You have been removed from Kudo mailing list for account: bob@gmail.com"
            },
            "Text": {
                "Charset": "UTF-8",
                "Data": "You have been removed from Kudo mailing list for account: bob@gmail.com"
            }
        },
        "Subject": {
            "Charset": "UTF-8",
            "Data": "Kudo email removal"
        }
    },
    "ReplyToAddresses": [],
    "ReturnPath": "",
    "ReturnPathArn": "",
    "Source": "donotreply@kudo.io",
    "SourceArn": "arn:aws:ses:us-west-2:1xxxxxxxxxx2:identity/donotreply@kudo.io"
}

bob@gmail.com is verified on my account (which is still in sandbox mode). donotreply@kudo.io is also verified on my account.

Edit: I just tested it by using the test email option in SES and it worked... still can't get it to send using the SDK though.