Going by the images of this incident, the debris has in all probability damaged the electric cables running along the front spar. Some of these wires would have powered the Electric fire shut-off valve of the Eng#1 and the EEC, hence the loss of control over the Eng#1.
I haven't read all the postings on this topic. The images beg the question how close was this incident to the paris disaster involving AF concord i.e. Debris penetrating the fuel tank resulting in uncontained fire and crash. Subsequent investigations led to the withdrawl of the concord due to design issues.