Originally reported in https://github.com/localstack/localstack/issues/2099, the CreationTime for CF stacks was hardcoded. This was fixed in in LocalStack itself (https://github.com/localstack/localstack/pull/2103), but is now also fixed in moto (https://github.com/spulec/moto/pull/2818).

I don't know what version of moto you're using, and whether it's acceptable to use dev-releases, but if you do: 

moto 1.3.15.dev550 should fix this issue, so the LS fix can be removed if you upgrade :) 
client = aws_stack.connect_to_service('cloudformation')
    try:
        result = client.describe_stack_resource(StackName=stack_name, LogicalResourceId=logical_resource_id)
        return result['StackResourceDetail']
    except Exception as e:
        LOG.warning('Unable to get details for resource "%s" in CloudFormation stack "%s": %s' %
                    (logical_resource_id, stack_name, e))
def retrieve_resource_details(resource_id, resource_status, resources, stack_name):
    resource = resources.get(resource_id)
    resource_id = resource_status.get('PhysicalResourceId') or resource_id
    if not resource:
        resource = {}
    resource_type = get_resource_type(resource)
    resource_props = resource.get('Properties')
    try:
        if resource_type == 'Lambda::Function':
            resource_props['FunctionName'] = (resource_props.get('FunctionName') or
                '{}-lambda-{}'.format(stack_name[:45], common.short_uid()))
            resource_id = resource_props['FunctionName'] if resource else resource_id
            return aws_stack.connect_to_service('lambda').get_function(FunctionName=resource_id)
        elif resource_type == 'Lambda::Version':
            name = resource_props.get('FunctionName')