Different response than in original server

Dear HAProxy Community!

Please, help me solve the problem.

I cant get real information from healthcheck if I use 'binded' port(25080). When something fails I always get 503- Service Unavailable, and its not meaningfull for me. But if I use original port(26070-as below) from my wildfly I have the real information for example 500-and proper message, 404, etc.
How can I pass the information in haproxy or is it possible to rewrite it some way?

frontend http-in
bind *:25080
maxconn 20000
option httplog
log global

option httpchk GET /rest/shopping/health “”

   server server0 cookie s0 check