Ive got a Vapor on mine, and I have the wire for that taped to the brake line with a nice smooth wrapped section of electrical tape about 6 inches long.
Dan

 

Yes it is BAD! the flexing can cause the hose to break at the lower fitting. It is made to flex in a huge loop above the triple clamp, not in that short span between the slider and the axle mount.

You should have the zip ties open enough to allow the brake line to slide upward and flex at the loop above the triple clamp, not tight at the bottom of the slider. you might be able to use three zip ties to make an eyelet. Make a loose loop for the brake line, then zip tie that loop to another zip tie around the fork leg - three makes it so the one around the line and the one around the fork leg are in the same plane (horizontal) with the other locking the two together in a vertical direction around them. That might work as a temp solution.

I would either get it to flex at the right place or I'd park it until I could get the slider guard where the line can attach properly.

You need to do exactly that.

 

I am curious what the rest of the bike looks like. What little I have seen really scares me.