I need to fly from HKG to DXB to CPH. Using Miles and Cash. Oneway in C class.

Only airlines from HKG to DXB are SQ via SIN or TG via BKK. From DXB to CPH I can either use LH via MUC or LX via ZRH or SK direct (but they don't seem to have any space on the dates that I want). I don't want to take OS either on their A320 aircraft for the 6+ hour flight to VIE.

Question... HKG-BKK or SIN, can I take F, and the rest on C? Is it still possible?