There are lots of factors that contribute towards deciding a clear winner in this kind of match up like health, terrain, etc. I never take on a Scorch at full health and if I do, it’s a hit and run. It’s not like a Northstar - Ronin match up up close or a Legion - Ronin match up from afar.
The outcome is not clear because of the jarring differences in mobility, area denial, melee range, health, clip size and choice of kit. But if a Ronin goes head on (i.e. without the element of surprise) against a Scorch that has more than half of its health, it is a dump thing to do in general.