The federal register for diplomas for secondary professional education and higher education in Russia can now be accessed at this site: http://obrnadzor.gov.ru/gosudarstvennye-uslugi-i-funkczii/7701537808-gosfunction/formirovanie-i-vedenie-federalnogo-reestra-svedenij-o-dokumentah-ob-obrazovanii-i-ili-o-kvalifikaczii-dokumentah-ob-obuchenii/.
You will have to scroll all the way to the bottom of the page until you see the text in red сaps СЕРВИС ПОИСКА СВЕДЕНИЙ О ДОКУМЕНТАХ ОБ ОБРАЗОВАНИИ. Click on the bar underneath with "Открыть" (Open) and the familiar online form will appear.
See original post for additional information about the database: https://theconnection.ece.org/NewsItem/1405.