I guess it's also a case of "letting sleeping dogs lie". US Aggressor and Adversary outfits have always painted their aircraft with red stars (save for a few notable exceptions). In some cases, their camo was or is close to Soviet/Russian aircraft, in others not. It's almost "tradition", nobody bats so much as an eyelid. Paint an Eagle in a scheme more or less resembling the recent Su-35 prototypes and it's pretty much business as usual. Announce tomorrow that the Aggressor and Adversary aircraft will be repainted to resemble Chinese aircraft and behold the sh!+storm that will ensue. The PRC will throw a hissy fit and the powers in charge in the US at all levels will have a lot of explaining to do to the media as to why they needlessly p!$$ off the Chinese. Far too much hassle for a very limited benefit in training realism (especially so with most of China's aircraft in rather boring greys anyway).
So, instead of unnecessarily opening a can of worms, schemes are kept as they were. Head honchos adjust training syllabi to reflect the most likely adversaries. Nobody complains. Everything's a-okay.
As for the VISMOD M-113s above, I don't recall either a Soviet or a Russian camo resembling anything close to this. Evenly spaced big stripes in green, black and brown. It doesn't get more "not looking at anyone in particular" than that.