I like the weathering because it does look as if it's chugging through the sand of some Pacific island.
And you can never say "never" with a Sherman. There are all kinds of mixtures of fittings on Shermans some of which have baffled experts for 60 years. This particular tank could be a very late 47 degree hull M4A2 just before the switch to the 76mm gun turret.
Or it could be that Dragon confused pictures of PTO M4A2 with M4A3 when researching the directions.