Mercenary Pilot has a point
Reviewing the pictures of the original fix over in flight global - The gimbled MLG actuator in situ and the picture of the piston end (complete with yellow goop) certainly does show that the cylinder was not replaced - nice new blue hoses used though! - If this was an "on aircraft" repair then you do open yourself to possible errors. It is always better to do an "on bench" assembly as everything can be layed out and accounted for before and after the assembly - no o-rings extra or no o-rings short after assembly.
Having worked at a landing gear manufacturer I can speak from bitter experience.
We would all love to know where the offending o-ring came from - any pictures yet of the item?