Gentlemen,
I can tell you from experience that Battlefront has this almost exactly correct. My credentials: 28 years of active service as an Officer of Marines, and three tours in Iraq. It comes down to the size of the propellant charge. The Panzerfaust 100 and Panzer Schreck are absolutely too large to fire in confined space. The Panzerfaust 30 could be used with a reasonable affect on the firing unit. The Panzerfaust 60 will definitely have a supressive affect on the squad, and is at the outer limit of what could be fired from a building.
As a company grade officer we tested firing the LAAW, a 66mm light AT rocket, in a confined space, ONCE! It was something not allowed in training after the test and was only "approved" for use in combat under extreme conditions.
Now, this may be a modelling issue of all or nothing from the game stand point, I do not know if the game has the ability to designate allowing the different Panzerfaust models to be used in buildings. Only Battlefront can answer that.
S/F
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