Looks like the Soyuz factory is far from the spaceport, meaning that the system is rail or ship transportable, so what about sending the whole Soyuz rocket to a suitable launch pad?
The problem is that the only 'suitable launch pad' is in the ex-ussr. Probably only Baikonur in Kazakhstan.
Also, theres no provision for getting soyuz rocket elements to a seaport, nor the handling facilities for middling heavy and delicate boosters.
Sure, something could be juryrigged, but by the time yoy
.negotiate among the US, russia and europe
.figure out what modifications will be needed where
.get the Colubri to e.g. Sevastapol, while carrying out modifictions to docks, the ship, launch pads at Kourou, arrange an appropriate supply of the special russian kerosene to kourou.
.getting the rocket on board the Colubri, and making it secure. Even with work down ahead of time, this will take some work.
.travel time from Sevastapol to Kourou. That will be a week or two there.
.getting the rocket off the ship to the juryrigged pad.
.fixing the unforeseen details of connexions between rocket and pad
Maybe, maybe its possible. But kourou wasnt set up to handle kerosene rocket fuel at the time. It wouldtake one of the ariane pads, i think there were two, out of service for some time. And the rush rush nature of the job means theres WAY too much chance for things to go wrong.
It would be easier to adapt a Soyuz spacecraft to an Ariane, and THAT is no easy job. Might well not be possible in the time allotted.
Ooo.. heres a really crazy idea. Launch a soyuz spacecraft on a proton rocket. That could provide enough delta v.
It would still be a rube goldberg mishmash, but at least everyone speaks the same language!