You cannot apply for a J-1 visa because you already expressed the intent to immigrate. You better follow through with your green card application.
I agree with Mr. Schmidt. However, it is unclear if you are subject to the two year residence abroad requirement imposed on some J1 visa holders. This can complicate the situation, since this bar to immigration must be overcome. Good luck.
This is general information, not legal advice, and does not create an attorney client relationship.
I agree with Atty Schmidt-- follow through the green card process, but talk to an immigration attorney to see whether you should go through consular processing or adjustment of status.
(626) 771-1078 Los Angeles Attorney Theodore Huang, Esq. This is not legal advice. No attorney/client relationship is established. Attorney Huang is licensed in MD; practice limited to federal law.