hehehe I'm evil now... I'm from the ones who say
"in the ending of the series , Alex must die in pro of the dramatic emphasis of the climax... " (add crepy laugh here)
Well with all of this poison inside him... my observation of his actual phisical status is: he's really Fu*** off and unable to move nothing bigger than a finger... this mean big problems... but he's still alive,those who want to see him alive dont loose hope.
My speculations are...
A.) Syverna crewmen did an accelerate close quartes battle training course (showing incredible skills, in weapon manipulation, dynamic entries etc etc), they board exile, face interior resistance and blockades... find alex, carry him away back to sylverna and escape...
(man I really want to see this, it would be espectacularˇˇˇ)
B.) Exile explodes/falls and Alex falls whith him while whispering "last of the mohicans" theme... and saying to maestro Delphine (who is in front of him) "if only I had one arm free..."
C.) Using a sharpened nail of the foot

(or anything else... but I don't think he has any cutting tools at hand) , Alex manages to cut off the roses and escape himself, while Exhile is hevy bombarded.
D.) Exile receives heavy fire, from vansip bombs, large caliber guns, torpedoes , SMR-2 missiles, 3 tomahawks, and one SCUD-III found intact in irak after the war, exile collapses and sinks... later examining the wreckage they find Alex still tied with roses saying whith his calm voice: "you are late"....
(this ending can combine with B )
difficult ending for Alex...