Are you sure it was Argentine?
There's two listed on Google that side of the river, but one is now a pub according to street view.
Definitely not the remaining one "La Casa Argentina" as I went in that one and it wasn't all you can eat and had rude waiters and ipads instead of menus.
There is a Brazilian one near the main square with prices that were about the same as yours with some Brazilian staff. I went in there a couple of times in 2015.
Couldn't remember the name, so not sure if it is the same business but definitely same place.
8 U Radnice
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