All praise is due to Allah, and may blessings and peace be upon the Messenger of Allah. To proceed:
“The One to whom dominion belongs” is an expression used to make a statement about Allah; it is not one of His Most Beautiful Names. As for “Owner of All Dominion” and “Doer of Whatever He Wills,” a number of scholars have counted them among the names expressed as phrases by which Allah may be invoked. This is the view adopted by the fatwa.
“The One to whom dominion belongs” is a statement about Allah, not a name
All dominion belongs to Allah. He has stated this about Himself, saying:
“Whatever is in the heavens and whatever is on the earth glorifies Allah. To Him belongs dominion, and to Him belongs praise, and He has power over all things.” [Al-Taghābun 64:1]
The expression “the One to whom dominion belongs” is therefore correct in meaning, but it is not an established name among Allah’s Most Beautiful Names. There is a distinction between a sentence conveying His sovereignty and a name established for Him.
Among the established names in this regard are Al-Malik (“the King”) and Al-Malīk (“the Sovereign”). Allah says:
“Exalted is Allah, the True King.” [Al-Muʾminūn 23:116]
He also says:
“He is Allah, other than whom there is no deity, the King.” [Al-Ḥashr 59:23]
And:
“In a seat of truth, in the presence of an All-Powerful Sovereign.” [Al-Qamar 54:55]
Abū Hurayrah, may Allah be pleased with him, reported that the Prophet, blessings and peace be upon him, said:
“Allah will grasp the earth on the Day of Resurrection and fold up the heaven in His Right Hand. Then He will say: I am the King. Where are the kings of the earth?”
Narrated by Al-Bukhārī (7382) and Muslim (2787).
“Owner of All Dominion” is one of the names expressed as a phrase
This name appears in Allah’s statement:
“Say: O Allah, Owner of All Dominion, You give dominion to whom You will.” [Āl ʿImrān 3:26]
A number of scholars have explicitly counted it among Allah’s names, including Al-Khaṭṭābī, Ibn al-Qayyim, and Ibn al-Wazīr. See Muʿtaqad Ahl al-Sunnah wa-l-Jamāʿah fī Asmāʾ Allāh al-Ḥusnā by Dr. Muḥammad ibn Khalīfah al-Tamīmī (p. 204).
What is meant here by names expressed as phrases is that a name may occur as a construction, such as “Owner of All Dominion.” Allah’s names do not all have to consist of a single word.
Ibn Taymiyyah mentioned examples such as “the Most Merciful of the merciful,” “Lord of all worlds,” and “Master of the Day of Judgment,” along with other expressions established in the Qur’an and Sunnah. He explained that invoking Allah by them is established.
Accordingly, “Owner of All Dominion” is counted among the names by which Allah may be invoked, according to the view adopted by the fatwa.
“Doer of Whatever He Wills” and its indication of perfection
Allah says:
“Indeed, your Lord does whatever He wills.” [Hūd 11:107]
He also says:
“He is the All-Forgiving, the Most Loving, Owner of the Throne, the Glorious, Doer of whatever He wills.” [Al-Burūj 85:14–16]
The cited source reports that Jaʿfar al-Ṣādiq, Al-Ḥalīmī, Al-Bayhaqī, and Ibn al-Wazīr counted this expression among Allah’s names. See Muʿtaqad Ahl al-Sunnah wa-l-Jamāʿah fī Asmāʾ Allāh al-Ḥusnā (p. 202). Al-Saʿdī also included it in his explanation of the divine names at the end of his Qur’anic commentary.
As Al-Saʿdī explains, it signifies the perfection of Allah’s strength and power and the complete effectiveness of His will. Whatever He wills, He does; no obstacle prevents Him, and He needs no helper. His will accords with His wisdom and praiseworthiness, so His acts combine perfect power with all-encompassing wisdom. See Tafsīr al-Saʿdī (p. 948).
Why must the full wording be preserved?
Ibn al-Qayyim explained that certain words, such as “the One who wills,” “the Doer,” and “the Maker,” are not to be adopted as names of Allah merely in their unrestricted form, because on their own they do not convey the intended perfection.
The revealed expression “Doer of Whatever He Wills,” however, indicates the perfection of His action and the complete effectiveness of His will. Its wording must therefore be preserved as transmitted, rather than replaced with merely “the Doer” or “the One who wills.” See Badāʾiʿ al-Fawāʾid (1/161).
What matters is that the name is established and that its meaning conveys the relevant perfection. A word’s derivation from an act attributed to Allah is not, by itself, sufficient to make it one of His names.
Conclusion
“The One to whom dominion belongs” is a correct statement about Allah, but not one of His Most Beautiful Names. A number of scholars have counted “Owner of All Dominion” and “Doer of Whatever He Wills” among the names by which Allah may be invoked. The fatwa adopts this view, while emphasizing that the full transmitted wording should be preserved.
And Allah knows best.