No. I didn’t do any code customization (neither in the free version nor the pro version), only selecting theme options via Appearance –> Theme Options.
Just to make sure, I completely uninstalled Clean Retina free version, removing all files, and reinstalled it again. I then activated it and looked at http://www.marysistersaustralia.com/events/, and it was all correct.
I can also switch to completely other themes (e.g. Twenty Fifteen) and the event page works correctly.
Do you have any experience testing Clean Retina Pro with The Events Calendar? Should it be compatible? If not, which other solution can you recommend for integration of events management in Clean Retina Pro?