All the Egyptians I know barely can lift a fork.
The point is, the body of the missile is relatively intact.
That is very telling. . .for weaponeers.
I can guess how it got there but my guess would have no fact as a basis to build on.
I know the weapon and I know its aftermath so when I say I think it might have been an IED, that “guess” is based on knowledge of the weapon.
(I am not convinced the reports are accurate. . .reporters are not to be trusted (enjoy): https://www.youtube.com/watch?v=A2sAFHBptJE
Even if we change our pretense to ‘MB TRIED and failed to knock out a building with a Hellfire’ we need to be asking how many more they have, where they got them and how long till they scrape up the cash for a platform that delivers.