I had a same problem on one of the senegal before, it tried to get into ome of my plastic rock that has a hole in it. I cover it witth a piece of cotton shirt that i cut off, just make sure the cotton is clean, twist it around make i alittle thick so it wont come off the hole. For treating the wound i only used aquarium salt and clean water. But i dont know what other fish you have and i dont know if they can take salt.
Im of the 'Better safe than sorry' category and say get rid of the decor and replace it with something that wont be an issue ever. Ive lost fish to badly designed decor and just wont risk it.