My 6mth old seems to be teething (gums red& swollen) I have tried cool teethers, orajel, and tylenol (acetaminophen). What can I do to alleviate those symptoms?

Avoid Orajel. The fda has recalled orajel due to deadly side effects in some infants. Roll a clean wet washcloth and place it in the freezer for a couple hours, then offer to the baby to gnaw on. The cool will sooth the gums and will clean the mouth at the same time.
Palliative care. It sounds like you have been working hard and doing everything correct. Make sure to encourage fluids and just support your child as best you can until he or she gets past teething. I would stay away from orajel, it only last for a few minutes and you have to keep putting more on. Tylenol (acetaminophen) will work better and last longer.
Natural. As a parent of 2, myself, it's tough. In addition to what you already attempted. You may want to try wetting a small cloth, squeezing the water out, and freezing it. They may find releif in biting the soft, frozen, cloth. Unfortunately, this is something time will heal.