I haven't been in security very long, but this is the most egregious backdoor I've seen in a commercial product. It's not even accidental, by virtue of the patch, which took 7 months to actually get deployed, was purely aesthetic and left the backdoor fully in place. They had a chance after it was initially discovered, to claim "oops debug functionaly, totally a rogue dev ignoring our super strict rules" but they decided to go all in instead.
It's not surprising that the company has no comment, but I sure hope this destroys any confidence that AMX's (potential) customers might have had in their products.