TomP ...you are right,#13 in reverse would play down to the landing area but if the green was placed in the hollow to the left of the current #12 green it would play slightly up.
The falloff behind the existing #12 green is strong, so depending on what height the new tees for #12 in reverse were built, the new hole would play uphill, probably 15' or so.
The drive on #9 in reverse is slightly uphill, the second shot would be decidingly more [not necessarily a bad thing].