The Vilna Gaon gave only three Haskamos on seforim in his life. Two of them were for seforim written by Rav Aryeh Leib Epstein. In one Haskama he calls Rav Aryeh Leib a “Rav HaDomeh L’Malach Hashem”. These words are often overused but not by the Gra. Rav Yehonoson Eibushitz called him Rosh Goilas Ariel, Rechev Yisroel U’Parashav”. Among his talmidim was Rav Alexander Ziskind the holy Yesod V’Shoresh HaAvodah. He was called the Ba’al HaPardes after a sefer he wrote. He also wrote the Sefer Ohr HaShanim detailing which Mitzvos you can do during different times of the day.
A sefer was printed with the Hanhagos of Vilna Gaon and the Hanhagos of Rav Aryeh Leib. Beneath are notes from Rav Moshe Shternbuch. A notable minhag he had for Bikur Cholim he says, when you visit a sick person you should give him your hand. While holding the sick person’s hand you should say “Yahiv Lei Yadei V’Ukmei”. (Literally he gave him his hand and he recovered. This is what the gemara (Brachos 5b) says happened when Rav Chanina went to visit Rav Yochanan who was sick.) Rav Aryeh Leib says that the first three words have Roshei Teivos of Yud-Lamed-Yud, which spells one of the 72 names of Hashem.
Rav Shternbuch says that he doesn’t know a source for this but certainly it is worth following the advice of a tzaddik sine it says “Sod Hashem Lirei’av”, Hashem share his secrets with those who fear him.