Thank you for your explanations. I can agree with your reasoning regarding the cafe. If you want to add the web design company maybe you can have a look at this page: https://wiki.openstreetmap.org/wiki/Tag:office%3Dit As I have no experience with the StreetComplete app I don't know if it's 
possible to do the planned edit with it. The editor on the website http://www.openstreetmap.org or a standalone editor like JOSM (https://josm.openstreetmap.de/) can definitely make the edit. JOSM is a powerful but unfortunately somewhat confusing tool for beginners.
I will close your note regarding the visibility of the cafe in Organic Maps. For the correct display in Organic Maps you have to wait some time.