Neither of those guys had the chance to fly the SPAD
So there is no blame to be assessed to either .
The interest in assignment of flight cause/effect to one or the other- is a mystery to me- Those old cats were simply the first to record the obvious. In fact - I would venture that the Egyptians knew the basics of some simple laws discovered by Newton- (action-reaction) and the Chinese likely noted speed/pressure relationships -
Let's face it -many discoveries are simply rediscoveries and some recent ones ( airplane/telephone /light bulb etc., were predictable discoveries and occurred in various places at practically the same time.
Just something to ponder -