Yes - this MILW loco is a product of "re-paint engineering"; it certainly is MTH's USRA
4-6-2 (which is actually a USRA Light, not a Heavy, as MTH insists on calling it), not
a MILW loco at all.
Having said that, this practice is one that enables us to have odd prototypes -reasonably-
represented; the other options are: build it yourself, or not have it at all. There would
be few takers on a true Chippewa Hiawatha - I'm not sure I even new about it.
Several years ago, using this same USRA tooling, MTH offered a beautiful, red/black/gray GM&O Premier 4-6-2, reasonably depicting the GM&O's ex-Alton Heavy Pacifics, which the GM&O re-lettered and kept the paint scheme. It wasn't "accurate" (the paint scheme was dead-on), but it was all that I was likely to get.
Lionel's "Alton" 4-6-2 is yet another inaccurate representation of these same locos earlier in their lives.
The MTH Southern Ps-4 is also the same loco; essentially accurate, in that case.
Your upcoming Hiawatha 4-6-2 is the same tooling as my GM&O 4-6-2. Enjoy it; it's
-far- better than nothing.
(MTH mis-represented the tender on the GM&O loco in the catalog - it depicted
a 12-wheel tender; the loco came with an 8-wheel - which is more accurate, BTW.)