It does say prototype WMMKII.... and I guess theres no timeline for when the suits were built and it does make sense considering Hot Rod has the star, IF it didnt I would think the Hot Toys MKII is the false WMMKII and Hot Rod was the prototype for an unbuilt suit that would be the MKII
That was flat out a mistake.
In reality, IP was the suit, and had the star on it.
Afterwards, during production, they released images of the "WM MKII" which didn't have the star.
In the meantime, during production, they used the IP mesh for the Hot rod.
None of that matters in movie continuity, as Hot Rod was first, then WM MKII, which was rebranded by the government into IP.
Hot Rod > War Machine MKII > Iron Patriot.