Can I add active member check to pool switch iRule?

Hello all, I have a request from a user where they would like a URI redirection to a separate 3rd host. The current pool has 2 hosts. The condition is if it matches the URI redirection, but the 3rd host is down, then go back to the original pool of 2 hosts. Is that possible? So far my iRule looks like this but I cannot figure out the 2nd requirement they need. Any help is appreciated. If there is a better way to do this otherwise, please let me know. Thanks!

ltm rule myrule {
  when HTTP_REQUEST {
    switch -glob [HTTP::uri] {
    "/myuri/abc*"  { pool myuri_pool }
    default { pool my-default-pool }
    }

} }