When were these accounts created?

Yours was made 6 years ago, but the other one it wont tell me.
do you control the other one?

Yeah, that was my old account. I'm tryin' to figure out the exact join dates of both accounts since I don't have the KA Extension anymore (it shown the exact join dates of a profile; I don't have said extension anymore because it was taken off of the Chrome Web Store).

The extension is now called "Extension for Khan Academy"

Oh, thanks! I didn't know they changed the extension's name until now. I'm now able to see the join date now. Thanks for the help!