Just because this mod and the models for it were made in free software does not mean that anyone can just take them. The creators of these assets, while the software is free, put time, hard work, and money into what they have made. No one likes it when someone takes their hard work, especially when they make it inaccurate. There is a chance that Chrome would have gave permission if it was edited correctly, but if it is not and is done without permission, him and others have a very good reason to be angry with you.