Load Balancer host based on User's CloudFront-Viewer-Country

We have a Cloudfront distribution whose origin is set to an application load balancer(by default). We want to set this load balancer host based on user's CloudFront-Viewer-Country. Below is the lambda that we're using to do the redirection eu_lb = "EU_LB_HOST" ap_lb = "AP_LB_HOST"

def lambda_handler(event, context): request = event['Records'][0]['cf']['request']

viewer_country = request['headers'].get('cloudfront-viewer-country')
if viewer_country:
    country_code = viewer_country[0]['value']
    if country_code == 'GB' or country_code == 'DE' or country_code == 'IE':
        domain_name = eu_lb
        request['origin']['custom']['domainName'] = domain_name
        request['headers']['host'] = [{'key': 'host', 'value': domain_name}]
return request

The issue is that we've setup a Route53 record to mask the url so let's say xyz.com is the url which points to Cloudfront host and from Cloudfront we want the request to go to load balancer but since there's a redirection at lambda@edge it changes the url to Load Balancer's host (xyz.com -> lb_host.com) We have some URL dependency at our code level which we cannot rectify as of now. Is there any way at Lambda@Edge level so that the URL doesn't change? Or is there any other solution to this? Kindly help us! Thanks in advance!