Agreed, I have done the same with my Victory MK Overdrive. Just make sure that your amp uses short to sleeve. I did exactly the same, connect a TRS cable (MK Overdrive has two cables so I can do everything the amp foot switch does). It was a bit trial and error ro work them out but doesn't take long.
May be I missed something but maybe not but I would like to swap the polarities. ie when I connected it up and turned on the Helix if I have a one switch switched between Lo and Hi gain the default on power on was Hi and I would prefer to change this to default to Low. If this can't be done it would be a helpful addition, or maybe I just missed how to do it?