Complex sentence: Contributing to their findings are two damage holes in the wreck of "U- 869", which are more consistent with the attack reports that cited two explosions than with the circle runner theory which would only explain one hole.
Split into simpler sentences: Contributing to their findings was the fact that there are two damage holes in the wreck of "U- 869". This was more consistent with the attack reports that cited two explosions versus the circle runner theory which would only explain one hole.