Why is CO being so 'cussed' in this instance.
It's a simple click of a few computer keys plus a few quid for the trouble.
For example Aer Lingus offer this change per this taken from their website:
'Name changes are permitted for €100/£80/$157 per person, and may be changed up to 2 hours prior to commencement of the journey.
Names must be changed for all flights in the itinerary'.
Maybe, just maybe, if you did a printout of this from the AL site - I'm pretty sure the BA's and Virgin's of this world allow name change too - CO might change their 'cussed' attitude.
Good luck.