S1 visa invitation letter

I am currently on residence permit (through a Z type) in Yunnan and trying to bring my wife to China so she can stay with me for more than 180 days. Last Thursday she tried to apply for S1 and the consular officer informed her that her documentation is incomplete. She has been asked to bring the invitation letter issued by the provincial government (as they explained to her the same type as I used to apply for my Z type, the letter which has been issues by local government in Kunming). After this request I have called the local government in Kunming and they explained that they can’t issue the invitation letter for my wife as the type of my Z type doesn’t allow that. They explained that there are two kinds of Z and the first type (professional) entitles the Z holder to bring immediate family members for more than 180 days, however the second type (standard), which is my type of Z, doesn’t entitle the holder to bring immediate family members for more than 180 days. After this surprising finding we have called the local government in Jinghong (Xishuangbanna) to ask which should my wife apply for as they previously claimed that L is ok. They confirmed again that L is fine and that they can convert it to Residence permit. So I am very confused now. I am afraid to let my wife apply for L type and to have her residence permit rejected once she arrives here. Any feedback from your side is highly appreciated.