Further thought.
If I am correct, and it is a half hole that is visible in each broken tube, why on earth would a designer intentionally make a vent hole in the leg tube? Shirley it would be better to vent it in the closures at either end?
Secondly, had the stress chap/chapess allowed for the fact that upon rotation at take-off, the mlg carries more mass than when at rest, and hence more tension in the back of the leg because it is now angled forwards? To explain. It's possible that at rotation it is probable that the mass perceived by the back wheels is more than the total static mass of the aircraft.