My brother and I completed our OW referral on Cayman Brac in 2001. Our first dive as certified divers the next morning started with dropping to a swimthrough that began around 95' (iirc) and dumped us out at 106'. You mean this isn't normal?
Here's the details. It was a boat dive and our instructor was now the DM for the 6 people on the dive. He briefed on the swimthrough and let everyone know we could skip it.
In his defence he did offer to skip it! The right answer to that would be, you as a certified diver should not have planed to go on a dive past your training and cert level. He should have probably followed this as well. Now I do see your still alive so it's all good. Cheers!