I got a reply back from the NIA saying:

Dear Sarah,

Thank you for your email.

You can pass any requests to the box office on the night of a show or email them to us at (don't PM me, I won't give you the e-mail) . We will pass them on to Tour Management on the day. As you can imagine, we do receive many requests of this nature and more popular artistes can be inundated. Sadly we cannot guarantee any acknowledgement from the artistes themselves as the decision rests with their management.

I hope this helps with your enquiry.

Regards,

Visitor Services Team

Has anyone posted Via Venue at the NIA Birmingham, and had a success/failure?

Edit: Birmingham in the UK

Cheers

Thumper