You are probably thinking HS32 "A Few Rounds".
This (standalone) scenario from the "Operation Veritable" HASL features some Sturmtigers of Sturmmörser Kompanie 1002.
In fact, this happened not far from where I live. Quite remarkable regarding the fact that only 18 Sturmmörser Tiger were produced in WW2, which were deployed in three companies (1001, 1002, 1003). In the beginning of October, I will visit the area together with Bruce Probst (from Australia, currently preparing for Arnhem Tournament) on a battlefield tour of the "Battle of the Hochwald Gap" for which I have won the local historian who did his PhD on the time of WW2 in the area. He also assisted in the TV-show on the
"Battle of the Hochwald Gap" in the "Greatest Tank Battles" series. In another battlefield tour of the Wesel Brigdehead I did with him a number of years ago, I actually met the old veteran of the 116th Panzer-Division featuring in that show. I thank the Lord that I have not yet been living at that grim time.
Maybe before or after the battlefield tour, I can get in a game of HS32 with Bruce.
von Marwitz