if I recall correctly from one of the many HIFS reviews that I had read in the past on many sites; believe someone mentioned they were able to see Disney fireworks from the property (didn't refer to which particular park they happened to be in though).
I would think it is definitely likely they could have because the hotel is just only 1 mile from the maingate and an approximately 4 min. drive. So, I think really considering where it is actually located the chances of you being able to see at least some of them anyway are indeed good.
I know when leaving WDW at night years past driving enroute to returning back to my offsite hotel and while heading up towards this particular direction in the car, I still had the potential of seeing fireworks at a distance that was going on.
Hope this helps.