Complex sentence: Goto and Gannosuke would follow suit in mid 1996 to rejoin FMW and IWA would start to go downhill losing much of the talent that Quiñones booked.
Split into simpler sentences: Goto and Gannosuke would follow suit in mid- 1996 to rejoin FMW. Subsequently, IWA started to go downhill after losing much of the talent that Quiñones booked.