It would be really great if there were a shortcode that could fetch the number of notifications awaiting the currently logged in user (like the bell icon in the wpForo menu does). Is this possible or is there any kind of workaround to make this work?
I'll suggest you check the "wpForo User Profile & Notification" widget. The widget can be found in the Dashboard > Appearance > Widgets > Available Widgets section, just drag it to a sidebar or click on it. More info here: https://wpforo.com/community/wpforo-announcements/wpforo-1-7-1-is-released/
Yes, I understand. I was just making a suggestion.