A couple of problems may devlop when cold water enters the inner ear through the perforation. 1. You may experience dizziness, nausea, and loss of balance, and 2. You may be more susceptable to middle ear infections. I did some research through DAN on earplugs and most of their physicians dont recommend ear plugs that totally block the canal. Some state that vented earplugs may work but studies are inconclusive. I found a couple of websites that may help,
www.proplugs.com has vented earplugs, and
www.proear2000.com has a mask that seals the ears and allows equalization through tubes from the ear covers to the facepiece. Check them out. Lastly, contact DAN and get their opinion. Good luck and dive safe.