No. This latch is an over-center design. The force resulting from this design holds it snugly against the bumper.
Here's my attempt at a legible force diagram, followed by a verbose attempt at describing its function.
Basically, the u-bolt on the swing-out is pulled tight against the hook on the bumper. The u-bolt's pivot point is slightly further aft than the handle's pivot point (rivet head) below it. As a result, as the u-bolt is tightened, it actually travels past the highest-tension position as the handle levers the u-bolt pivot point toward the vehicle, resulting in a small horizontal component of the resultant force. This small horizontal component holds the swing-out snugly against the bumper and it is impossible for the the swing-out to open until the u-bolt is moved past the center rivet.
I hope that's slightly comprehensible.
The long and short is--no, there is not a requirement for a latch to lock down an over-center latch as long as the swing-out doesn't flex so much while driving that it allows the u-bolt to momentarily lose it's tension. That's the only scenario I can envision where the backup latch might prevent the over-center latch from spontaneously opening.