Sadly I don't think he cannot be trusted with credentials too much; he has been accused of plagiarism [1] and has promoted crypto ponzi schemes [2].

About his supposed academic papers; Scopus says his h-index is 0 and only seems to have 2 publications [3]. He might be claiming that for self published articles or something.

[1]: https://english.elpais.com/international/2023-11-18/javier-m...

[2]: https://www.ambito.com/politica/javier-milei/que-es-coinx-la...

[3]: https://www.scopus.com/authid/detail.uri?authorId=7004452442