@ RayPublisher:
The language is clear: "Governing Body members sign gift Bibles for public officials".
Definition of SIGNATURE (Merriam-Webster)
1 a: the act of signing one's name to something b: the name of a person written with his or her own hand
Since the caption clearly says they were signing Bibles, and since we know the WTBTS publishes Bibles, their own NWT version, we can be certain they were not signing the country's guest registry. We can only go by the careful choice of language used by the WTBTS.
Now, if however, you are talking about a gift inscription, the language to be used for such an act should make a clear distinction between the two ideas. To suggest it might only be a gift inscription is to merely suggest it might be a gift inscription, and you could be correct.
The photo, however, highly suggests a formal book signing, for how many givers of books as gifts do so in the context of a photo op and sitting formally at a table simply to inscribe a message of appreciation to government officials and/or politicians unless it was a tacit act of political alignment or acquiescence?
Which actually brings us to your reminder about the NGO scandal.
This entire trip to Cuba by the governing body smacks of schmoozing with government officials, acting out of harmony with their stated Scriptural position when it comes to religious leaders and their dealings with government and politicians, or as the WTBTS puts it in the book, The Nations Shall Know That I Am Jehovah, chap. 16 p. 297 par. 11, "hobnob with the politicians" in order to further "kingdom interests".
The GB loves to point their self-righteous finger at the Catholic clergy, for example, who cooperate "with [the] business and political groups in trying to persuade their parishioners that all was well". (WT 12/01/80)
Why is it the governing body can violate their own standards by hobnobbing with governments, and sign oaths of allegiance to them to further kingdom interests when my JW child must suffer ostracism by peers and teachers for not saluting the flag?
Whatever the case may be, signing or inscribing, this shameless public display of hobnobbing with government officials only lends more weight to the UN NGO issue. Surely, we can reasonably agree on that point.