OK, I checked out your links, and they don't seem to have the text of their proposed amendment other than this vague statement:
We are calling for an amendment to the US Constitution to unequivocally state that inalienable rights belong to human beings only, and that money is not a form of protected free speech under the First Amendment and can be regulated in political campaigns.
So, then, the National Association for the Advancement of Colored People cannot spend money as they choose, because as a corporation, it doesn't have any rights, correct? And for humans, speech will be limited to using your voicebox, and not distributing pamphlets?
It would be useful to review the actual Citizens United case: a group of people organized as a corporation were selling an anti-Clinton video close to an election, for which they were prosecuted. If dissing politicians is bad, what exactly is the point of the 1st Amendment?