That would have been right as the SNES and Super Mario World were released in America.
Maybe they didn't think it had a chance?
I doubt that had anything to do with it, since the game shares many characteristics with Super Mario Bros. 3, which is arguably the greatest video game of all time. Also, Armadillo was released in Japan after the Super Famicom and Super Mario World were released there.
Seems they published a bit more in Japan in their short life.
Despite the lack of titles published by IGS after 1993, we don't know the whereabouts of the publisher or what happened to them, since there is no evidence of that company going out of business or coming to an end. So it would be unfair to say as if it were a fact that the company's life was short.
That publisher was a Japanese publisher called IGS, which I think is a different company than a Taiwanese game company of the same name.
That is almost certainly correct, as the Japanese IGS stands for "Information Global Service", while the Taiwanese one stands for "International Games System".