SC inside flow - How to access values?

I am trying to use Server Connect within a flow (dynamic event linked to button - not separate flow). Basically I want to click the button, retrieve some data via SC and then use some as a parameter for a JS function.

When I add SC to a flow created within a dynamic event, there is no option to select its values in the data picker in subsequent flow steps. Furthermore, there is no Output option for the step either.

I have just updated to 2.9.1 and it is the same