הקצין רבי שמואל היליס,פרנס ועד ד ארצות ומנהיג הקהילה בבריסק - Was his wife the daughter of Rabbi Pinchas Halevi Horowitz?

Good question; I don't know the answer (yet). On another note; You Refer to the Moginei Shlomo as R' Yehoshua Heschel Charif. IMHO he should not be called Heschel. 1. In most sources he's referred to only as R Yehoshua Charif. 2. That could cause some confusion with the "Rebbe R' Heschel", also of Krakow.

Jacob Mordechai Posner
Regarding the name of Meginei Shlomo, so it is written in his profile in geni,That's why I wrote his name that way,
By the way, also Rabbi Shmuel( mentioned above) according to Naftali Wakstein, his last name was not Hillis, but it is only a nickname
Similar things exist in many profiles where a certain person is given a last name and this is not true, it is just a nickname