Columbia is pretty expansive. I too agree that Columbia Deep or Pinnacles is definitely not a suitable dive for a first timer. However, what I often do is this. If I have an open water student on the boat, along with experienced divers...the instructor and the student are dropped in a shallower section of Columbia. There is a ridge of beautiful coral heads at a depth of 40 to 60 feet inside the wall. The wall and this ridge are separated by a sand flat, so it works out well. The instructor and the student are dropped in this shallower area, and the other divers and divemaster are dropped over in the deeper section. What often happens is that the experienced divers make their way over to this shallower area at the end of the dive and all of the divers surface in the same vicinity. This section I am referring to is not Columbia Shallows proper, but it is a shallower section of Columbia usually with very mild currents.
Scuba Du may do this same thing, but I cannot confirm that. What I would encourage you to do is to make sure that they are not taking you to Columbia Deep. If so, then pick another day to start diving or look for another option.
I hope this helps!