only other thing I can think of is drawing a line on the chart from departure airport to IMT and flying that IMT radial to the airway. You could than define that point as IMT19036 and file direct to that point.

But....
that only works if you have a usable VOR within distance

I guess you could use (for the sake of the computer accepting the route) a VOR 120 miles away to define a point on the passing airway, and file direct to ABC230120. But since you cant use the VOR for navigation do to the range can you navigate basically by dead reckoning to the point where you pick up the airway?