The behaviour you noticed seems to be normal for a two-speed Strida.
Maybe slightly different from bike to bike, as you can see below:
Crank does touch bolt, passing is possible…
Bolt blocks the crank, passing impossible (without violence)…
The reason is the different (straight) shape of the two-speed cranks.
The original (bent) crank is lying upon the two-speed crank:
You provided the best solution by yourself. Do NOT walk backwards!
What I mean is:
Do not PULL your Strida, PUSH it!
Anyway, you will notice that the rolling stability of a “pushed” folded Strida is much better than that of a pulled one.