Ilona tried her best to remove the bloodstain from Mason's shirt, but she didn't know the first thing about cleaning clothing. She used a bar of soap and some water and scrubbed as hard as she dared, but the improvement was minor. She was working at the very back of the ship, away from prying eyes, and didn't dare ask anyone to show her the right way.
The Captain of the ship shouldn't be washing clothing for a common sailor. It wouldn't matter that the only reason it was stained and ripped was because of her.
When she finally gave up on her cleaning, Ilona went to look for her mother, one of the only people on board she felt she could ask to sew up the hole. Ilona had never sewn a single stitch in her life, so she didn't bother trying herself. She would likely end up with nothing but knots.
She just had to do her best to hide it from Anja that the shirt belonged to Mason. Her mother would never approve.