What is the creed of Ahmed Al-Rifa'i, and is it permissible to ask for Allah's mercy upon him?

Al-Rifa'i is Ahmad ibn Abi al-Hasan, the shaykh of the Ahmadiyya and Rifa'iyya Sufi orders. He resided in "Umm Ubaydah" and had some understanding of the Shafi'i madhhab. He was renowned for his righteousness, being a devout worshipper and ascetic, who frequently sought forgiveness. He passed away in the year 578 AH. Al-Rifa'i was not known for his knowledge of the Sunnah or the sciences of the Salaf, and there is no confirmation that the books attributed to him were authored by him. As for the group that affiliates itself with him in this era and past eras, they are people of misguidance and false beliefs. They innovated satanic acts after his death, such as entering fires and carrying snakes. Al-Rifa'i himself and the righteous among his companions were not known to have performed these acts.