by Fleuri
1) I would say that you would be allowed to influence because you are a single faction now playing for joint victory. The wording in the base game rules doesn't account for that situation, but I think that it's intended that an alliance is considered a single faction on this matter.2)The rules indeed seem to imply that, but I guess that wasn't the designers intention.
Both are excellent questions, that need an official clarification. Great job pointing them out. Have a +1.