Dear t.delacour,
it sounds like you've done excellent in diagnosing yourself... I can personally not see any symptoms of which you describe, that don't fit with the diagnosis ofcuboid syndrome. My main references for this is localized and visible signs of inflammation, pain at push off in stride, a sensation of something being shifted. The faint, high frequency vibration (excellent description by the way!) could potentially represent some involvement of the sural nerve... The only thing that surprises me is that you can eliminate almost all pain by walking on toes... But, no injury behaves the same... I'd say you're correct.
It is worth a try to get the cuboid bone mobilized or manipulated. You'll probably find a youtube video called something like cuboid whip or cuboid manipulation. They usually respond pretty well when successful, successful more dependent on your particular injury rather than the technique I'd suggest... A physio, chiro or osteopath could help you with this. Or even try to mobilize it yourself and see how it responds. If it responds, I usually see a lot of improvement within first session, if not better after two sessions, then try something else.
Cuboid syndromes also usually responds very well to conservative management (move within pain/adapt activities/rest/treatment) and will not heal faster if you see a doctor. If you'll run in 10 days? My general take on this would be that you're likely to exacerbate it, and potentially have a longer time of recovery after that run, than if you rested. But, I find it very difficult to give a meaningful prognosis on this without really seeing you. Hope this answers some of the questions you had, and maybe some of the other therapists in here will skip in with some helpful comments as well. Good luck with your recovery anyway!
Kind regards,
Sigurd Mikkelsen