Given he can only not be charged over the Testogel, if the panel decides Sutton's word is less reiable than Freeman's, I would say it is about the most important piece of evidence myself. The MPTS panel will see Sutton claiming to DCMS/Paliament nothing in the jiffybag, no wrongdoing - even taking offence at the suggestion from the DCMS there was any wrongdoing, while all along he's signed the affidavit with Lawton that the Jiffy contains Triamcinolone and the reason they are all there in the first place.
Is there a reputation to uphold for Daily Mail? Obviously Daily Mail are insured against defamation claims but Sutton won't be and if it is revealed Lawton went with a made up contents from Sutton which seems the only possible outcome if they release the affidavit to GMC, is 'that' something they will just let Sutton take the blame and absorb the embarrassment themselves, or will they want to protect their own integrity by fighting in the the Courts with Wiggins? Remember Wiggins has already stated this is with the Courts last year already. I highly doubt Wiggins himself had the power of Medical Act to force Daily Mail to release the affidavit to him though. It has ramifications far beyond Freeman & Sutton for Daily Mail imo.