Ultimately, it worked! Thanks for the info. I was trying to stop on a failure of a remote sequence or a regular step, but skip over normal sequence calls within StationCallbacks.seq. I used the following precondition to my GOTO END step.
(TypeOf(Parameters.Step) == "SequenceCall") && ((PropertyExists("Parameters.Step.TS.SData.RemoteExecution")) && (Parameters.Step.TS.SData.RemoteExecution==False))