I doubt badr-3 would be fired in multiples more than 2. I have seen video evidence from where Al-Quds Brigade firing them in pairs with a slight delay. Probably on a setup similar to an image I attach below.
I wasnt trying to question who or what caused it but mainly just to inform that rockets of that power do exist and have been used against Israel for years. I havent seen a trustworthy source of video to draw any real conclusions, the one I seen earlier appeared to show a rocket intercepted and then an explosion along the same path, but again I cant say if that is even real. Hitting a hospital of all things seems almost too coincidental to happen by accident / misfire.
Two Badr3 rockets at a 2021 Gaza parade:
One about to be intercepted over Israel 5 months ago, the larger rocket at the bottom.
View attachment 96093
This apparently isnt just Hamas involved, every terrorist/resistance organisation in Gaza took part in this, except apparently Al-Qassam Brigades, this is based on footage uploaded by members of each group during and after that first day attack showing them actively taking part within Israel.
People arnt sure if they planned this together or only joined in once the attack started but either way members from all but one group were seemingly involved within Israel killing and taking hostages.
They would have access to any weapon within Gaza effectively if that is true.