I think what he's saying is the Sorc force ran and jumped out of the first spawn when defending and pulled sniper to him on the top of the middle partition. I've been up there and it's over 30 m to the doors. Maybe a marksman sniper could still reach them but I seem to remember targeting people up there and they were 40 m away when on the doors.
This. And snipers have several 35m abilities and a 40m ability.
And btw I wouldn't consider this an exploit at all, just a wise use of map design, if that is its even possible.
It is an exploit, especially if you're stealth and sitting up there telling your team which side is capping. That = unfair advantage.