Spelling of Vietnamese names in formal context

I am a professor and I have a Vietnamese student called, say, Nguyen Hoang Thang. How should I write his name in the official documents, such as his diploma or transcript? How should his name be indicated in published scientific journal articles he authors?

(Not duplicate of this question because that question is not about formal rules, and the answers mainly say "different people prefer different spellings of their names", which does not answer my question.)

His passport specifies:

Full name: Nguyen Hoang Thang

It is clear to Vietnamese native speakers (him included) that Nguyen is his family name, Hoang is his middle (additional) name, and Thang is his (main) given name, roughly corresponding to Kennedy - Fitzgerald - John or Bianchi - Lee - Mary.

I do realize that I can ask him, but even if John Fitzgerald Kennedy prefers to be called Jack, as a professor I cannot indicate his preferred spelling in his diploma -- there must be formal rules for this. My question is about these formal rules.

So how should we write the name of my student in the following formal contexts?

The transcript certifies that:
Last name: Kennedy, First name: John Fitzgerald (or John? John F.?)
Last name: Nguyen, First name: Hoang Thang? Thang Hoang? Thang? Thang H.? H. Thang?

The degree is bestowed upon:
John Fitzgerald Kennedy
Nguyen Hoang Thang?
Thang Hoang Nguyen?
Hoang Thang Nguyen?

Authors of the journal paper:
John F. Kennedy
Nguyen H. Thang?
Thang H. Nguyen?
H. Thang Nguyen?

Authors of the journal paper:
J.F. Kennedy
Nguyen H.T.?
T.H. Nguyen?
H.T. Nguyen?

Per Wikipedia on Vietnamese Names there is a convention for this.

Vietnamese personal names generally consist of three parts: one patrilineal family name, one or more middle name(s) (one of which may be taken from the mother's family name), and one given name, used in that order. The "family name first" order follows the system of Chinese names and is common throughout the Chinese cultural sphere. However, it is different from Chinese, Korean, and Japanese names in the usage of "middle names", as they are less common in China and Korea and do not exist in Japan. Persons can be referred to by the whole name, the given name or a hierarchic pronoun, which usually connotes a degree of family relationship or kinship, in normal usage.

Due to the frequency of the major family names such as Nguyễn, Trần, and Lê, persons are often referred to by their middle name along with their given name in Vietnamese media and youth culture.

Examples: Nguyễn Tấn Dũng is the former Prime Minister of Vietnam. Nguyễn is his family name, Tấn is his middle name, and Dũng is his given name. In formal usage, he is referred to by his given name ("Mr. Dũng"), not by his family name ("Mr. Nguyễn"). Likewise, the famous general and military leader, Võ Nguyên Giáp, is referred to by his given name, i.e. "General Giáp".

Despite other Asian naming conventions following the use of the family name as the primary index, Vietnamese names tend to follow the opposite for Indexing purposes per CMOS

According to the English-language Chicago Manual of Style, Vietnamese names are indexed according to the final given name and not according to the family name, with a cross-reference placed in regards to the family name. Ngô Đình Diệm would be listed as "Diem, Ngô Dinh" and Võ Nguyên Giáp would be listed as "Giáp, Võ Nguyên".

The CMOS convention seems to be used in many other places, too. Though there’s some debate on the subject.

Since this seems to be the most commonly used convention in English and lines up with Vietnamese usage, I’d suggest giving his name as Thang, Nguyen Hoang on formal papers (Thang, NH when abbreviated in a citation).

Nguyen Hoang Thang on a diploma. This will probably line up better with his passport as well, rather than trying to shoehorn it into English.