[angiosperm]

The doesn't say whether the C-145As built in Poland for the US Air Force still had the fault, or the SkyTrucks built until 2019. We might guess that since the fault wasn't in the plans, they would not get it, but that might depend on whether they were built in the same factory as HA-LAJ, with the same practices.

It seems as if were both engines to fail, either one prop would be feathered and the lift spoiler on that side extended, or neither prop would be feathered. Presumably the pilot could feather the props himself. It is not apparent whether this would extend both lift spoilers too, or if those were controlled separately.

[foobar1962]

The design drawings did not have the fault, but the engineering drawings used for building may have. They were done by different teams in different organisations at different times.

[nvy]

I doubt they have the same fault. It's common practice in NATO air forces to use lock wire or another type of anti-backoff mechanism on screws and bolts subject to vibration.

If the original design lacks this it would likely have been embodied as a fleet wide modification/design change.

[p_l]

It would be also quite normal for design plans to just specify that it should be "screwed here", depending on standard practices to use the standard screw locking.