Does AWS SSM agent cloudwatch resource:memory event?

Am picking ECS optimised instance(ami-05958d7635caa4d04) in data plane of ECS in ca-central-1 region.

AWS Systems Manager Agent (SSM Agent) is Amazon software that can be installed and configured on an Amazon EC2 instance, an on-premises server, or a virtual machine (VM). SSM Agent makes it possible for Systems Manager to update, manage, and configure these resources.

In my scenario, Launching a ECS task in ECS optimised instance(ami-05958d7635caa4d04), causes resource:memory error. More on this error, here. Monitoring ECS->cluster->service->events will not work for me, because cloudformation roll back the cluster.

My existing ECS optimised instance is launched as shown below:

"EC2Instance":{
            "Type": "AWS::EC2::Instance",
            "Properties":{
                "ImageId": "ami-05958d7635caa4d04",
                "InstanceType": "t2.micro",
                "SubnetId": { "Ref": "SubnetId"},
                "KeyName": { "Ref": "KeyName"},
                "SecurityGroupIds": [ { "Ref": "EC2InstanceSecurityGroup"} ],
                "IamInstanceProfile": { "Ref" : "EC2InstanceProfile"},
                "UserData":{
                    "Fn::Base64": { "Fn::Join": ["", [
                        "#!/bin/bash\n",
                        "echo ECS_CLUSTER=", { "Ref": "EcsCluster" }, ">> /etc/ecs/ecs.config\n",
                        "groupadd -g 1000 jenkins\n",
                        "useradd -u 1000 -g jenkins jenkins\n",
                        "mkdir -p /ecs/jenkins_home\n",
                        "chown -R jenkins:jenkins /ecs/jenkins_home\n"
                    ] ] }
                },
                "Tags": [ { "Key": "Name", "Value": { "Fn::Join": ["", [ { "Ref": "AWS::StackName"}, "-instance" ] ]} }]
            }
        }

1) Does aws ssm agent installation required on ECS instance(ami-05958d7635caa4d04) to retrieve such cloudwatch events(resource:memory) with aws.ssm cloudwatch event rule filter? or Does aws.ec2 cloudwatch event rule filter suffice?

2) If yes, Do I need to explicitly install SSM agent on ECS instance(ami-05958d7635caa4d04)? through CloudFormation...