ثُمَّ الصَّحِيحُ أَنَّهُ ﷺ إِنَّمَا رَأَى رَبَّهُ بِفُؤَادِهِ، لَا بِعَيْنِهِ
The preferred view is that he ﷺ saw his Lord with his heart, not with his eyes.
This is a preferred theological interpretation within a disputed question, not a declaration that no other attributed positions exist. Fuʾād here refers to the heart and ʿayn to the bodily eye.
A description of inward vision should not be turned into proof that the entire Ascension occurred only in sleep. Bodily travel and the mode of a particular vision during it are different claims.