Cloaking is always not free, But what i can suggest is, either way you can make a fake landing page to show to google, and block all traffic from google ip to the redirected landing page.
This is a little bit blackhat, but it does work 100%. But you have chance to loose account, when it is revealed.
But if you choose to create a e-mail optin page, or landing page, you wont get as conversions, like you redirect to offer page.
I am 100% sure, it does work. Dont do iframe, because google wont like iframe sites. They never approve your site.