@Korting for now put in a one-line representation saying that the alleged contravention did not occur, submit this via the TFL website and take a screenshot of the confirmation page.
In the morning call TFL on 0343 222 3333 and ask for the CCTV, they will send you a DVD in the post.
The TMO is The GLA Roads and GLA Side Roads (Southwark) Red Route Consolidation Traffic Order 2007 (https://drive.google.com/file/d/1AFuwdX8e18gHL3gZfZmVZnJwC2Kvq6vj/view) as amended by The GLA Roads and GLA Side Roads (Southwark) Red Route Consolidation Traffic Order 2007 A202 GLA Road Variation Order 2014 (https://drive.google.com/file/d/1YlrWhyO9kuYXqYrOMP9JxlzflpCqe_SD/view), the relevant entry is at page 2 of the 2014 Order:
A202 CAMBERWELL NEW ROAD, the north-east side, from a point 1 metre north-west of the common boundary of No.177 to 183 Camberwell New Road and No. 185 Camberwell New Road to a point 1 metre north-west of the common boundary of Nos. 171 and 173 Camberwell New Road.
This is all wrong, No.177 to 183 Camberwell New Road is the Co-Op here https://maps.app.goo.gl/xhtKS3GwDRSiubeX8 so the bay should start 1 metre from the boundary between the Co-op and the house at number 185, the bay should run to the point where the laundrette's door is seen here https://maps.app.goo.gl/91gXwv4zPfAi5jWV6
TFL might argue that because you were stopped where a bay should be marked this doesn't matter, but it's definitely worth running the argument at the tribunal that the road is not marked correctly (and the sign should be facing traffic and it isn't).
And then there's the issue that the Notice of Rejection template used by TFL is flawed, that's a tried and tested ground. I think TFL have now tried six or seven reviews and they've failed every time.