The xorg-client package uses your PKG_SYSCONFBASE (which defaults to 
${PREFIX}/etc). XDM gets its configs from ${PKG_SYSCONFBASE}/xorg/xdm/, so 
be default look at /usr/pkg/etc/xorg/xdm/Xservers and related. (I am just 
replying to emails about that; I am not replying about the real problem.)

 Jeremy C. Reed

p.s. Please do not include the entire large previous email when replying.