Bloomberg never indicated that the imaged chip wasn't the backdoor chip. The article repeatedly suggests that they're actually showing the backdoor chip.

https://assets.bwbx.io/images/users/iqjWHBFdfxIU/iNO3klzCOEj...

This image is captioned "Microchips found on altered motherboards in some cases looked like signal conditioning couplers."

You can easily find the article yourself here https://www.bloomberg.com/news/features/2018-10-04/the-big-h...