A handy way to do this in the future is the lcn=yes or the bike network relation since that road has green bike route signs that are also present in Guelph's official ArgGIS data.  It makes sense to keep it designated due to the presence of the green bike route signs.

I actually went ahead and updated the roads nearby which are part of the local bike route, as well as their speed limits. As a consequence, that should help your routing problems. :)

Please avoid using "designated" or any other changes to fix routing issues (unless they accurately represent what's on the ground) in the future which should be resolved in the app's code.