It is possible to launch Survey123 and open a form from Collector for ArcGIS using a link to the Survey123 form in a pop-up. This process is described in Esri's online documentation here. All seems to works exactly as described when working w/ iOS (e.g., Collector 20.2.1, Build 2844; Survey123 version 3.9.149 ) but problems arise when using Android devices (e.g., Collector 20.2.0, Build 2952, Survey123 version 3.9.149). Specifically, the hyperlink does not function as a hyperlink (typically shown in blue font) but is displayed simply as text (gray font).
There is a simple workaround for this which is to use a custom attribute display when configuring your pop-up and then putting the link to Survey123 there as a hyperlink. The process is described in this GeoNet post.
Still, this seems like a simple fix to make on Esri’s part and could save developers lots of wasted time if resolved. Please vote this up to tell Esri to fix it!
Links
https://doc.arcgis.com/en/survey123/reference/integratewithotherapps.htm
https://community.esri.com/groups/survey123/blog/2016/07/30/understanding-survey123s-custom-url-sche...