My initial thought is you pulled back on the elevator before it had proper flying speed and stalled. Since you did not have the chance to trim it out, it may have had just enough elevator to keep flying but on the edge of a stall. When that little bit of up elevator was applied, it was just enough to raise the nose, exceed the critical angle of attack for the airspeed being flow and one wing just gave up and quit flying. When it rolled over on its side there was not enough airspeed to fly knife edge (not to mention no rudder) which allowed the nose to fall through and meet head first with terrafirma who usually wins that battle.

IMHO, think you are trying to make too big of a jump in planes going from a 3-channel rudder/elevator plane to an EDF. You need to work up to the EDF by flying something with ailerons and aerobatic like a Formosa or similar type of plane. Learn to fly aerobatics first and master maneuvering the plane while working up to the EDF.

EDF's can be a handful - I did a maiden on one recently and fought it through most of the flight. It snap rolled and spun on me but luckily I was able to recover it literally less than 1' off the ground turning final. When I went to flair it snap rolled again but luckily it was only a couple of inches off the runway (I promptly landed it and told the owner to hand it on the wall).

Hogflyer