The victory conditions are Quests (TranscendenceVictoryQuest.lua in this case).
Even if you don't know lua, making the changes without workaround is easy in this case. At the top of the file, there is:
local FIRST_TECH_TYPE = GameInfo.Technologies["TECH_TRANSGENICS"].ID;
local SECOND_TECH_TYPE = GameInfo.Technologies["TECH_SWARM_INTELLIGENCE"].ID;
local THIRD_TECH_TYPE = GameInfo.Technologies["TECH_NANOROBOTICS"].ID;
Just swap out the tech names, but make sure you keep the rest of the formatting intact.
Quests must be imported into the Virtual File System (click on the file and then look at the properties window), and they must be imported via the content tab as Type Quest (you must type that manually after choosing the File in the lower field), and the Name-field must match the name of the file, but without the extension, so TranscendenceVictoryQuest in this case.