Plain and simple,,, they have stolen from you.
OK, let's switch positions here.
Let's say you have stolen something from them,,, how would they react?
Their legal team would be banging at your door demanding compensation.
I would strongly suggest you chase them over this.
And it has nothing to do with "get rich quick" but it does have everything to do with moral standards,,, which sadly seems to be lacking in a lot of businesses these days.
Good luck,,, and give 'em hell.