Early missile bases were extremely vulnerable to attacks; all one needed to do was find the right location, and a simple ignition source could send the entire base sky-high. The fuel for V1—octane and for V2—liquid oxygen and alcohol were highly flammable, making them difficult to manage. As a result, many of Germany's early rocket experiments ended in various rockets self-destructing on or near the launch pads. Only someone as desperate and inventive as the infamous Corporal with his mustache could consider using such dangerous and immature technology to try to salvage his nation's fortunes.
The FZG-76 didn't burn fuel, which made it a lot safer than its immature predecessors, but because its fundamental design was a direct copy of the V1, it also inherited another drawback, leaving an opening for the enemy to exploit.
This insurmountable vulnerability was the angled track launch.