But it won’t be a uniformly higher orbit, because there’s only one event where energy was added to the fragments. The perigee will still be in LEO and anything that’d raise the apogee to a point where the new orbit would be stable for a decade would require so much energy that it’d vaporize the satellite on impact.

My local PC hardware store offers assembly and setup services for ~20€. Includes installing and updating the OS and drivers, as well as stress testing to verify that the components perform as expected. More places should offer that option, really. Especially if they also sell pre-built PCs that are assembled in-house.

17cm/s seems awful low. Is that its speed relative to Didymos?

Your math ain’t inherently wrong though. Without strapping a torch drive on that thing it ain’t going anywhere.