There's no way to view this in-game and it's unlikely to be added back in again. Information is definitely outdated and you shouldn't really take it to heart.
The Beta Testers was a rank in the BanTech Systems group. People in the rank used to test upcoming updates and new features coming to SCR in the future, alongside other games owned or being developed in association with BanTech Systems.
Testing usually takes place on a separate server. However, there are some exceptions, as the 158 was tested on the live games.
The first use of Beta Testers in SCR was with the Big Update, in which around 40 people were chosen to test the update and its features. Testing lasted around a month.
The second use of Beta Testers was with V1.1. Here, More testers were added to the Beta Testers rank. This testing period is the longest, lasting slightly over four months.
Finally, the beta testers tested the Class 158 for Connect. More testers joined during this period. All of the testers tested the first trains with interiors in SCR in live servers. Since then, the testers have been used on various occasions to test new trains, and also the 1.4 update.
However, during the beta testing period of the V1.4, a group of anonymous beta testers (whom later formed the notorious "SCR Leaks", now also the domain of SCR haters) leaked this update in its entirety, including the assets included, documents and information regarding the update. Their actions had angered many other players, and also the HRs of SCR, and is somehow believed by some players the reason the release of the 1.4 update was delayed.
As those beta testers refused to stop leaking confidential development information, in around January 2020, BanTech decided to terminate the Beta Testers Programme, along with the suggestions and bug reports zone in his BanTech Systems website.