Hello, Keith.
I thinks there's little doubt that the yardman is incorrect and that he is confusing a swing keel 25 with a delta keel 25+. I can see where the nomenclature would make it easy to confuse. But they are very, very different boats. (I own an E26-2, which is nearly identical to the 25+, but with a slight modification to the forward part of the cabin and with the traveler moved from the bridgedeck to above the companionway.) Just thinking of how the E25+/E26-2 is constructed, I think it's nearly impossibe that Ericson would have offered it in a swing keel version, granting the massive amount of re-engineering that would have taken for such a modification. They did offer a shoal vs. deep draft model of the delta keel E25+/E26-2, but that kind of mod is pretty trivial.
I've never seen an E25 in person but they look nice enough in pictures. But they layout is rather different than the E25+, so perhaps that's not what you want.
Happy hunting,
Alan Gomes