The major hurdle you will encounter is that the AAT will be expecting source code for an Adapt course. That's not just text content and assets, but source code for the framework and plugins that you will be using to present that content. Since Articulate 360 doesn't use any of this, there is no direct path for import. I know of no third-party conversion tool. Perhaps someone else will recommend tools and techniques.
This thread leads me to believe that exported files are not editable:
I have not dug through an exported Rise package, but I hoped that you could find text content that could be copied and pasted into a newly created Adapt course. Unlikely if everyone's saying you can't edit it--but I'd still look!
If you begin to explore what's exported from Rise 360, remember that Adapt will have its own plugins for SCORM (adapt-contrib-spoor) or xAPI (adapt-contrib-xapi), so you can export web-only output.
If you learn more from your colleague about importing/converting Rise 360 courses, please continue this thread.