Hi Gary,
You'll want to verify Pinterest just as the instructions say. Google doesn't actually use the Pinterest verification for anything - verifying just allows you to link to your domain from your Pinterest profile - google's gonna crawl and index it either way.
So google will know the link is there, but honestly, don't count on social profile links like this making much of a difference for SEO. However, if you're active and connected on that network, pinterest can sure drive some referral traffic to your site. Hope that helps!
