My introduction to cabbage rolls was from first generation Polish folks.
No beef for them they diced and mashed up fresh Kielbasa , pronounced by the natives as --Kilbas-ey.
Some would buy the links and have the butcher grind it up, others smashed it themselves or diced it.
Every one made cabbage rolls different deciding on what part of Poland they came from. Then the fact that as first generation Americans they messed around with Grand Pops recipe a bit. Allot depended on what was available to them in the area they lived in the OLD COUNTRY.
I have eaten them made with mashed potatoes instead of rice, some with turnip or carrots. Seems one can stuff the leaves with most any root crop. Onions, potato's , turnip, carrots, rutabaga, garlic and even radishes.
We Americans are use to some form of tomatoes or sauce but I have eaten some excellent rolls with chicken gravy.
Ground Hot Italian sausage is a good substitute for beef If you have no Kielbasa and if you want something that is in no way bland.
Cabbage rolls are one food that can be played with and the possibility's are endless.