Have you tried looking on their own website? Plus you would be better suited asking RealScout own support to see if it is possible to integrate the IDX with Wix to begin with, as there is no point trying to get this to work if they won’t support it themselves.
If you can use their API, if they have one available, then you can expose your site to that and work from there.
https://support.realscout.com/hc/en-us/articles/217437466-Adding-RealScout-Widgets-to-Your-Specific-Website
https://support.realscout.com/hc/en-us/articles/202521865-How-to-Get-RealScout-Search-Widgets-on-Your-Website
