Had no luck with it so he has now taken it home to try and find/remember what password he used.
As I said we did the google 'forgotten password' thing and they sent a code to his phone.
But entering this code and setting a new password did nothing, it kept coming back asking for the old password.
TBH we may have been trying to reset the wrong account.
He has various gmail accounts with different addresses/passwords, he's been setting up a new google account everytime he gets a new device.
And most are associated with the same mobile number, which is not a smartphone.
So for now I've told him to try and remember what email address and password he used for that tablet.
Failing that he's going to have to get back onto Time2 and see if they can do anything, at least they are in Blackburn and not China.
PS. I had another friend who was 'locked out' of her Windows laptop last month. At least with Windows I could force it into troubleshooting mode without a password and do a complete reinstall.
I was looking for the possibility of some option like this to get into the Android tablet without a password.
Further talking it turns out that before he came to me his daughter had factory reset it, and then somehow he set up a 'sketch' type password by making a random squiggle on the screen.
Of course my factory reset should have cleared that.
I'm reading that I may be able to connect it to my laptop and completly reset it with a new account - if he had certain settings on the tablet.