I never got around to finishing Madness Returns myself, but what I did play back in the day was mighty enjoyable. It looks like the game went back on sale on February 28, with one Steam review celebrating the game's return writing: 'I literally spent over 100 dollars just so I could play this game (while it was taken off sale), only for it to come back cheaper. Keys have been going for a wild variety of prices during its absence, with some as high as $200. While the game has been available on Origin the whole time, people were still keen to have the game in their Steam library.
The game was originally delisted from Valve's client sometime in late 2016 thanks to some squiffy verification issues on EA's end.