Lucas!
Typically when a plugin like this is used to save data to a specific product (images, notes, or in your case, video) that “save” is storing that information in the product’s meta for use, so it should already be there for you. Judging by the code snipped provided, this is happening in..:
update_post_meta( $post_id, '_woofv_video_embed', $woofv_data );
With the video link being stored in the variable “$woofv_data” in this specific function, and “_woofv_video_embed” being the meta key you would use to access this value later.
If you would like to see what is going on within your product’s meta, there are plugins like JSM’s Show Post Meta that will actually display a list of all your product / other post type’s meta keys and values below. Having something like this when developing can be pretty handy as it takes out a lot of the guesswork when trying to assess what information is or isn’t being stored, and where it’s stored at.