Ms. Gold

Unlike the AI Moore who's in charge of managing the entire CDCA Bureau, Gold evidently does not possess such advanced analytical computational skills. Not to mention, she was designed and created over two decades ago. Even when compared to BOX—who's part of the 'Android Mechanic' series as well, albeit a newer model—she also appears slow and outdated.
It is seriously fascinating that such an almost-archaic robot could continuously remain in operation for decades. Part of the report noted that there was a possibility morphic field pollution had caused her framework or logical circuit to change.
After ONEderland's situation basically stabilized, a researcher expressed a desire to conduct a comprehensive inspection for Gold, and she agreed to it. However, the result was out of anybody's expectation—prolonged morphic field pollution did not change any of her internal components nor affect her program much.
This model of nugget mech was created with the intent of accompanying human gold diggers, and she accomplished it impeccably. It seems the best explanation for this would be a coincidence, or perhaps, a miracle.

"Gold thinks, BOX have functionality issues. Why not, accept inspection?"
"There isn't any functionality issue with me! I will not accept these dubious inspections! I will not!"
It's unknown when it began, but somehow, Ms. Gold became insistent that BOX's hostile, teasing attitude toward the Conductor must be due to a virus in BOX's program. As such, she kept persuading BOX to return to its manufacturer to undergo a program inspection.
In contrast to that, BOX does not believe that anything is wrong with its program at all and thus constantly turns down Gold's suggestions. This sparked off an intense, unending chase aboard between the two robots of different sizes and styles.
From a maneuverability standpoint, the Bionic Operator X, which is BOX's model, is much smaller, making it ideal to play the role of humans' assistant. Meanwhile, the Android Mechanic Nugget Mech—Ms. Gold's model—has various Outdoor Gear integrated, hence making it much larger and heavier. In such a chase, Gold doesn't have the advantage, which makes it understandable that she would lose.
However, what BOX doesn't know is that Ms. Gold had already been serviced and upgraded by COLUMBA when boarding The Eternal. COLUMBA not only replaced her exterior with a much lighter and sturdier material but also added a special weapon module, "Rocket Punch," for her.
Hanging upside down on the ceiling of the front carriage, BOX only made it in time to see the armor on Gold's arm glow when activated...

After the ONEderland Hotel incident came to a close, ONEderland received a grant from out of nowhere, with a transaction remark of only two words—"Remember her."
As it was a truly vague remark, Ms. Gold eventually decided to use this money on the construction of ONEderland's historical archive. For robots, to "record" is to "remember."
However, a problem arose during an unexpected juncture of the construction. The downtime Ms. Gold experienced prior had caused her memory module to be significantly damaged, resulting in her having only a small portion of the documents and reports left saved in her memory. Meanwhile, owing to the lack of upkeeping throughout the years, ONEderland did not have much relevant memory retained either.
Ms. Gold was extremely troubled by that, and when The Eternal crew noticed it, everyone offered various advice. One of them ultimately stood out and attracted her attention: "How about seeking help from Mr. Peter Hwang and Baxter? With their influence, they should be able to locate those past gold diggers and gather some stuff that can suffice as historical materials, right?"
Needless to say, Peter agreed to Gold's request with a bitter smile, getting to it right away while mumbling how he would have to owe people favors again. Conversely, Baxter nearly spat out his cactus drink upon hearing that request. His eyes widened in shock as he exclaimed at her outlandish idea, though he still made great contributions later.
Of course, not everyone who was contacted was willing to help. Some of them weren't keen on recalling anything concerning ONEderland, and some hung up after going on a tirade, but at the same time, a good number of them did send back some items and even materials too.
In these materials, The Eternal crew discovered a special photograph of young Peter and Baxter standing before ONEderland's entrance with arms around each other's shoulders. Gold stared at the photo for a long, long time until she finally asked for a special commission from The Eternal.
"Please, bring Peter and Baxter, back to ONEderland. Gold, want, take photo. ...With everyone."