Sigh.
After surmounting multiple difficulties, including finding someone willing to get to my place and explaining to a clueless grandma over the phone how to wire a monitor to a PC, the server was brought back up.
Still not sure what exactly have happened, but stupid Windows kept defaulting to "launch windows restoration tool (recommended)" on reboot, instead of "Just start Windows" (which is why the much easier "press the glowing thing until it stops glowing, unpress, count to five, then tap it again" instruction failed to produce results), and the logs just cut off without any clues.
Anyway, server should be up and i disabled the oxygen for now.
If anything is broken, last backup was on March 23rd, crash happened on around March 24th-25th.