CGB - the values you quote refer to height at the TDZ (touchdown zone), I have not checked but I suspect this is the TCH (Threshold crossing height). This is much further on than the Decision Altitude, which, acknowledging errors that may be present, is a minimum 200 feet height. If obstacles or higher ground are present this DH is modified accordingly.
I am no expert on approach design but the TDZ does not makes sense. Can you elaborate what this means?