Currently, I am looking into Net::DAV::Server's new() function, which is where the executions seems to take the wrong path due to some variable being filled differently when working as a subclass..
Investigating...

Update: could extract an error, its in new()'s eval: "Undefined subroutine &Foo::_dav_child called at Foo.pm line 164" which is in my copy and pasted Foo.pm::propfind().
Why didn't use base import the _dav_child() function??

package Foo;
use base Net::DAV::Server;

sub propfind {
 # copy of the original propfind() from Net::DAV::Server
 # do something
 _dav_child(soemthing);
}
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