It just hit me : This model of service bot is based on Death Trap, which was made by Gaige about a decade ago. (As it is explained in different echo log spanning from borderland 2 to borderland 3)
Typheon Deleon bought two bots on Pandora before going to Nekrodefeyo a few decades ago.
Meaning he apparently bought those two bot, before Gaige designed the first prototype.
Conspiracy, I tell you