Cimmaron bowls cannot be mixed with any other model, as is usually the case with any toilet model and brand series.
I don't know where you live, but here in San Diego, the Kohler Wellworth no longer qualifies for the rebate. The list is much shorter. To qualify, generally, a toilet either has to be a pressure assist ( e.g. Wellworth Elite) or it has to be one of the so-called golf ball toilets: Cimarron, Champion, Toto G-max, etc.)