Hi Hayley
Are Collector and Survey123 pointing to the same feature service? If so, there would be no need to launch collector from survey123. You would just interrogate the survey data directly in Collector.
If not - while it is possible to access completed surveys using the survey123 inbox - it is not possible to pass answers into Collector for viewing purposes. Survey123 can't push out the existing answers.
I hope I this is helpful and let me know if you have any further questions.
Thanks
John