Sole source SB found non responsible...what now?

Has anyone encountered a long-time recipient of sole source contracts (25+ years) suddenly be found non-responsible? We were working on a follow-on IDIQ, and due to recent concerns, requested DCMA perform a financial capability assessment. DCMA recommended no award, so we submitted a COC to the SBA. SBA has declined to provide a COC.

 The contractor refuses to sell their data rights so we are stuck trying to figure out how we can support the systems currently in the field or the upgrades we had planned (including a $1.2M delivery order at time of contract award). This 5 year IDIQ was supposed to carry us until the replacement systems were chosen. I'm not sure where to go from here... wondering if anyone has found creative ways to fulfill a requirement while in a similar situation.