sort of covers the composite -front
In-situ composite repair builds on basics : CompositesWorld
My point is there are many ways to repair and inspect major- minor damage.
However- the damage shown so far at Heathrow may well be above reasonable limits- cost- etc.- includinjg electrical- smoke damage - time- cost via insurance and no doubt a few hundred other issues not touched on here
787 and other composite model airplanes with major composite structure have been around for quite a while.
It is NOT like fixing your fiberglass corvette of the 60's and 70's, nor is the old story about epoxy fumes- lighting strikes- etc really applicable.
Hope this tamps down at least Some of the flip flapping