That is interesting, have not had a client or heard anyone use a page for product landing pages.
1) Redirecting is not allowed in Google Merchant Center. The page submitted must be the one the customer lands on without redirect.
2) If you don't have many products, consider submitting a manual spreadsheet as data feed. In this case you can use the actual pages as product url.
3) Consider changing how your web shop works and make it more default, ie products instead of pages
Hope this helps.