slim, at least one similar statement was published earlier, in 2007:
7 Here the slave is called a steward, a word translated from a Greek term denoting “the manager of a household or estate.” The collective steward would not simply be a group of intellectuals who explain interesting points from the Bible. In addition to providing nourishing spiritual food “at the proper time,” “the faithful steward” would be appointed over the entire body of Christ’s attendants and assigned to manage all of Christ’s interests on earth, "all his belongings.” What would this entail?
8 The slave’s responsibilities include the supervision of the material facilities used by Christ’s followers to carry out their Christian activities, such as the world headquarters and branch offices of Jehovah’s Witnesses, as well as their places of worship—Kingdom Halls and Assembly Halls—throughout the world. More important, the slave also oversees spiritually upbuilding programs of Bible study at weekly meetings and periodic assemblies and conventions. At these gatherings, information on the fulfillment of Bible prophecies is dispensed, and timely direction on how to apply Bible principles in daily life is given.
9 The steward’s responsibilities also include the supervision of the all-important work of preaching “this good news of the kingdom” and making “disciples of people of all the nations.” ...
https://wol.jw.org/en/wol/d/r1/lp-e/2007245
Interestingly, in 2001 they interpreted the belongings more narrowly:
‘The faithful slave’ has been ‘appointed over all his master’s belongings.’ These include facilities at headquarters in New York State, U.S.A., and the 110 branches now operating worldwide.
https://wol.jw.org/en/wol/d/r1/lp-e/2001051
But in most cases, this term didn't explicitily refer to the organization's assets:
Jesus had so much confidence in the slave class that he appointed it over “all his belongings”—that is, all his spiritual interests on the earth. (2006)
What are the belongings over which the newly crowned Master appointed his faithful slave? All the spiritual things that belong to Him here on earth. For example, two decades after Christ’s enthronement in 1914, “a great crowd” of “other sheep” was identified. (2004)
"Kingdom interests on earth" (2002, 2001, 1994)
"So, what are “all his belongings”? These are all the spiritual assets on earth that have become Christ’s property in connection with his authority as heavenly King. This definitely included the commission to make disciples of Christ, with the grand privilege of acting as representatives of God’s established Kingdom to all the nations of the world. ...the slave class has been appointed over all the Master’s belongings — his Kingdom interests on earth — and these belongings keep on increasing. (1993)
Dislaimer: this list isn't exhaustive, and I cannot guarantee I haven't overlooked some relevant — and different — statements.