This response is based on the information provided.  We suggest you discuss with your contracting team, program manager and/or legal department as appropriate. 

The purpose of NAICS are to identify the type of work the government intends for a given action and for companies to identify the type of work they are capable of.  It is your team's job to determine through the selection/negotiation process to determine if an offeror is capable of performing the work.

There is no law prohibiting creating a contract action simply because the solicitation NAICS and offeror NAICS do not match.