The officials behind Palm Beach County Convention Center’s current developmental phase haven’t found scandal so much as scorn. Three of five development groups rejected from the bidding process filed protests saying the county showed an “arbitrary and capricious” tone when it dismissed their bids for the business. FRI Investors of West Palm Beach, Grove Street Partners of Atlanta and Rose Development of Michigan all wrote letters dated Sept. 18 saying county officials didn’t know how to evaluate the prospective builders. “Procuring a hotel developer is different than procuring a copy machine,” Grove Street Partners’ James Stormont wrote. Shannon LaRocque-Baas, assistant county administrator, said a hearing could be held on the issue in November.