I don't see how the Russians could save the HST and upgrade it???
The Soyuz can't get to an altitude of 600 Km and can't get to the 28° orbit; even if Kourou could launch Soyuz launchers, it's far too early for manned flights. Besides, the Soyuz can't carry the instruments for the HST at the same time.
The HST depends on the Shuttle and that's it.
Putting it in a higher orbit (where it won't do anything but sleep once only 2 working gyros are left) or returning it in the Shuttle are far less important than servicing HST in order to upgrade it and if that's not possible, it will be grieving time.

Raoul