What? No, you're wrong. She says she made them "before you escaped" and says something along the lines of "No hard feelings, but you did try to kill me." That sets the time frame after GLaDOS died but before you escaped with Wheatley. They are also tested in the same time frame, as you see plants in their test chambers.
Edited it, although not much.
No, the co-op bots' campaign continues from the end of the single player campaign. And snot is correct.
But that makes absolutely no sense with what GLaDOS said. She talks as if they were made after her death, likely in fear of Chell (as the only subject left) going after her. (Before she discovered the human vault) but before you escaped, as she said.
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