They are bid spotters.
If you picture the sales room as the lower half of a clock (the top half being the ring and auctioneers) EC stands where the “4” is, Ralph is around “5:30” and Roger is at “7”. I usually sit right next to Roger (or Mike when he’s on that shift).
The Keeneland auctioneers–especially Chris Caldwell–occasionally interact with the bidders, but they never call them by name.