If you're referring to the "manipulated link" that included changing the "25K" to "50K", this is different. AFAIK it's not a manipulated link. The tiny print/footnote on this app also verifies you'll get 50k bonus points.
Perhaps it's not really a "public offer", but anyone lucky enough to stumble upon it would get the 50k.
I would try it, but my Amex Plat hasn't been closed long enough.