I am not sure if I follow the exact problem here.
If your material is set by a parameter in the object then there is no need to REQUEST anything, as you already have the parameter value.
Otherwise, can you create a property with an expression that splits the material name into its code and description components?
Then you can schedule that property value.
This method could be used on other elements (walls, slabs, etc.) as well as objects.
Versions 6.5 to 22
Dell XPS- i7-6700 @ 3.4Ghz, 16GB ram, GeForce GTX 960 (2GB), Windows 10
Dell Precision M6800 - i7 4700MQ @ 2.40GHz, 16GB RAM, AMD FirePro M6100 (2GB), Windows 7 64bit