Actually - the Egyptian Pharoahs looked like that dummy character due to inbreeding.
He could have died from any number of diseases that were rampant during that time period.
The broken leg is not indicative of an infection. Tons of people at that time suffered broken legs and did not die from them.
All in all they have very little evidence to support their theory, but of course with modern scientists the truth and real evidence is irrelevent.