What is the "right" way to proceed?
The "right" way depends on what you want to do. From what you stated in your question, I assume that your following FAR 13 procedures for commercial items with a value under #25K. You can resolicit with some evaluation factors or negotiate on price only with all 3 vendors. It will probably be easier to ask for a lower price from all 3 vendors.
Open full Question Details
In the future, IAW FAR 13.106-1(a) (2) When soliciting quotations or offers, the contracting officer shall notify potential quoters or offerors of the basis on which award will be made (price alone or price and other factors, e.g., past performance and quality). Contracting officers are encouraged to use best value. Solicitations are not required to state the relative importance assigned to each evaluation factor and subfactor, nor are they required to include subfactors.