Yes, you can. This article outlines How to Transition to a Raw Diet.
Yes, thawing is a good idea but don’t cook it because you defeat the purpose of raw by cooking out the nutrients.
Dogs Choice stands behind its food. Occasionally a dog just doesn’t take to raw or they may have a particular protein allergy. If you are not fully satisfied, please contact us. If you bought the food through a reseller, you will need to return or exchange product through them.