I believe your TA is mistaken.
2. Reprotection Agreement with Thai Airways (TG)
Passengers originally booked on the cancelled SK-flights with SK/117-tickets issued until 16FEB07 may be involuntary rerouted to TG-operating flights in lowest available booking class in same service class as originally booked.
Economy Extra class (Y) passengers may be rerouted to TG Premium Economy class (U-class).
Reissued E-tickets and paper tickets shall be marked "INVOL RTNG 735D"
Insert an OSI-line with the following information:
INVOL REROUTE DUE TO CNCLD SK FLIGHT SK…/DATE