Workforce and Survey123 are a powerful combination together, it's even baked right into the set up of the Workforce project. The struggle I was having with it was after a user submitted/closed the survey they opened, they then had to manually switch back to Workforce.
Today I discovered that you can go in and manually edit the URL template in the Assignment Integrations table to include callback=https://workforce.arcgis.app to make this work, but what would be incredibly helpful and simplify this process for a lot of people I'm sure would be to add a checkbox or option on the Survey123 Integration set up menu in the project itself to turn on the ability automatically return to the Workforce app.
A previous idea that took this a step farther and included the ability to have it send a value such as a Work Order ID back to Workforce which I also love, but can see being a lot more complicated. That can be found here: https://community.esri.com/t5/arcgis-workforce-ideas/callback-between-survey123-and-workforce/idi-p/933155