The US has been firing HELLFIREs from humvees since 91. The Navy has been firing from ship mounted launchers since before that.
Twin rail launchers that fit standard NATO hard points are part of the system and can be modified, there is no minimum forward airspeed required for launch. The missiles and launch equipment are normally found together in shipments to foreign militaries in aid programs.
Launching from a vehicle is not anything new. If they have more of these, they will figure out how to make them detonate next time.
The US has. . .not the Egyptians.
And it takes a heck of a lot of integration and testing to get the system right.