The only list I've seen is from the ISP forum slides publicly available on the BTWholesale website ("Go to market" section, then "See past events and resources"). The most recent is from September, and yes, the list is quite short, and does not include devices specific to a particular ISP nor the Openreach modems. Many manufacturers don't seem to bother putting their devices through the testing process. The list from BTWholesale will only include things tested via BTWholesale, some things might have been tested by Openreach directly.
While devices supplied by ISPs are required to have passed the testing, things sold to the general public probably won't have been, manufacturers won't probably bother unless it affects sales. And the list of approved devices isn't even publicly available, people would have to rely on manufacturers like Zyxel advertising that their devices have passed.