The clean office is just a Potemkin village for the investors.
Potemkin village
idiomAny false construct devised to disguise a shortcoming or improve appearances.
Origin
first recorded 18th c.Calque of Russian потёмкинская деревня (potjómkinskaja derévnja), named for purported fake settlements erected at the direction of Russian minister Grigori Aleksandrovich Potemkin to fool Empress Catherine II during her visit to Crimea in 1787.
The company built a Potemkin village of high sales figures to hide the fact that they were losing money.
The government presented the renovated city center as a Potemkin village, masking the deep poverty and decay that persisted in the surrounding districts.