I’ve been told personally by the bands old manager Alan Niven that years ago the band members would get the Tour Manager Doug Goldstein to sign things on their behalf, apparently they used to think it was a great joke.
That said given Slash’s involvement in the game I would imagine he signed them all personally.
Here’s some pics of Axl, Slash and Duff’s (his is terrible) signatures that I have personally got myself.
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