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What you're not taking into account is the differences that bullet weight and construction will have on expansion even at similar velocities. Due to it's extra weight, the .357 Magnum loading has not only more energy but also more momentum which, all else held equal, will cause it to penetrate more.
Similarly, the fully jacketed bullet of the 9mm will likely behave quite differently than the semi-jacketed one used in that particular .357 Magnum loading. Semi-jacketed .357 Magnum loadings like the Federal load you linked to or the very similar Remington and Winchester 125gr loadings routinely fragment moderately by shedding their jackets in large shards starting at 6-8" penetration with an 80-100gr lead core continuing on for a total penetration depth of 11-13".
High-velocity 9mm loadings with lighter bullets (115gr or less) on the other hand often expand rather violently with severe fragmentation very early in their penetration with a total depth of only 6-10" unless bonded or all-copper bullets are used. While Buffalo Bore did, at one time, use the excellent Speer Gold Dot bonded bullet for most of their JHP loadings, the stock photo in the link you provided appears to be the Montana Gold JHP's which Buffalo Bore began using for some of their ammo due to difficulties in obtaining Speer Gold Dots during and after the ammo shortage of '08-'09. While Montana Golds have excellent reputations as accurate target bullets, their performance as self-defense bullets reportedly leaves much to be desired. Montana Golds are not bonded bullets and since Buffalo Bore is likely driving them well beyond the velocity window that their manufacturer intended, I would be surprised not to see significant fragmentation and comparatively shallow penetration.
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