How do I drain the remaining 7 inches of water left in my easy set pool since I already drained it to the drain valve plug level using a garden hose?

You could always use a garden hose to siphon it down to less than an inch. Just fill the hose with water, put your thumb over the end and a friend do the same to the other end. Then you place your end in the pool. Have your friend go to a spot lower than you and lay the hose down. Then you should both remove your thumbs. The water will immediately begin to flow and will do so until the end in the pool sucks air. The remaining less than an inch can be removed with a shop vac used in wet mode. Hope this helps.