Usually, alcohol wipe is not advisable to use. I am afraid to try. Ha!I found black dots on one of my nude color patent leather shoes too. I dont know where they are from.. But i wipe them off easily with a medical use alcohol wipe..
I had that happen to my RI brea...the dots were in the vernis so I was unable to remove them...
I have a few of those on my patent blue Chanel. I took it to Chanel and they said maybe they were there when I first bought it. NO HELP.
I think it might be transfer if you wore it against something black. I think that's how mine did it.