Who encounter this problem?

My friend got her Germany passport then came to USA to do postdoc with J1 visa. She applied for the green card after she got a faculty postition. and Her 140 was aprpoved. Now she encountered a problem with her 485 application. The immgrant officer asked her to provide J1 waiver since she hold J1 visa.
I think the J1 waiver just work for Chinese not for her. Because she is Germany now. doesn't it?

Who can give some addvise to this case?

Thanks a lot!