Frankly, other than the lease of the Ricoh prohibiting the leaseholder (i.e. Wasps) from sub-letting the stadium, the negotiations between Wasps and City are NOTHING to do with the Council, so how the FUCK can they be a complication?
I'm firmly of the belief (from the coincidence of timings, Giblet's twitterings, etc) that the EC contacted the Council to inform them that they were undertaking a preliminary investigation under Article 107, and required certain information to be provided, at which point the Council leaked it to Wasps who shat themselves and pulled out.
I hope that Wasps have seen sense and realised how long-term this investigation may be, or some other assurance (but NOT indemnification by SISU) - or sheer fear - has brought them back to the table