Having this exact issue, hopefully someone responds.

i couldn't either i was already on alpha tech but still coulnd't elect it, did some digging and found the tech id, using cheats to give myself the tech allowed me to get the decision
i asume you are no longer playing that playthrough but incase you need it in the future or incase someone else has the same problem
research_technology tech_dm_ancient_palace

引用自 -KoTrT-Sir Balin：

i couldn't either i was already on alpha tech but still coulnd't elect it, did some digging and found the tech id, using cheats to give myself the tech allowed me to get the decision
i asume you are no longer playing that playthrough but incase you need it in the future or incase someone else has the same problem
research_technology tech_dm_ancient_palace

Thank you, i'll probably need to use that in the future, it might be a mod or two thats messing stuff up but i'm useless with that stuff.

Appreciate the help