No way!
the dark L shape on your picture are ventilation apertures, so they can't be covered.
The maximum depth is about the thickness of the sound deadening material at approx 10-12mm (around half inch). The amp is 42mm deep (1.7 inches) by 160 x 170mm. (6.3 x 6.7 inches).
The dark rectangle is the horizontal part of the hook which is used to attach the cover. This seems to be the defining depth as it is approx 10mm.
If this wasn't hooked in, the cover would sag and probably could not support the weight of the amp.
Not looking good at the moment...