Update on Sebastian:
He has his check up on his eye yesterday afternoon and the ulcer hasn't gone away. Now they are doing this treatment where they took some of his blood, spun out water (I think he said water, I should have listened better) and made a serum out of it. We have to put a drop of his own blood serum in his eye every 6 hours and then we go back next weekend to re-check again.
Hoping this weird blood thing works! In the meantime, just call me Dr. W