Does Sheikh Ibn Baz believe that a disbeliever must pronounce the Shahada and perform ghusl, and that ghusl for a disbeliever is obligatory?

Scholars differed regarding the obligation of a disbeliever's ghusl (ritual bath) upon embracing Islam. Some deemed it obligatory, while others restricted it to cases that necessitate ghusl (such as janabah - ritual impurity from sexual discharge). However, the Malikis and Hanbalis held it to be obligatory, citing prophetic narrations such as the Prophet's (peace be upon him) command to Thumamah ibn Uthal and Qais ibn Asim to perform ghusl after their conversion to Islam.

The Hanafis and Shafi'is, on the other hand, considered it recommended, not obligatory, due to the lack of widespread transmission of a command for it, despite the large number of people who embraced Islam.

In conclusion, the preponderant opinion is that ghusl is obligatory.

No statement from the esteemed scholar Ibn Baz on this matter has been found, but the Hanbali school of thought holds it to be obligatory.