When ores went down for three hours at 7am (Berlin time), no one contacted the team and if I didn't have IRCCloud app on my phone, this outage probably would have been two hours longer. SRE/RelEng should have access to phone numbers of several WMDE staff who are responsible or on-call for production services.
The other way around also hold true. WMDE staff don't have access to contact list because they don't have access to officewiki. Technically WMDE staff who have access to prod can get it via mwscript getText.php officewiki 'Contact List' but that doesn't seem nice.
(Adding managers of the teams)