In this commentary on the Visuddhimagga, regarding the section which discusses nibbāna, Ven. Dhammapāla writes this
yadi nibbānaṃ nāma sabhāvadhammo atthi sattasantānapariyāpanno ca, atha kasmā catumahāpathe sabhā viya sabbasādhāraṇā na labbhatīti āha "maggasamaṅginā pattabbato asādhāraṇa"nti. "asukassa sammāsambuddhassa kāle uppanna"nti evaṃ purimāya koṭiyā abhāvato appabhavaṃ. maggabhāveti ariyamaggassa atthibhāve. bhāvato vijjamānato laddhabbato.
(560) If nibbana exists as the state of individual nature and it is included in the continuity of living beings, then why is it not available as common for all just like assembly hall held at the cross road? Therefore to answer it there is the sentence, “ It is not shared by all because it can only be reached by one who has possessed the path (maggasamahginapattabbato asadharanam ).” It is uncreated (appabhavam): because it has no beginning, such as, “It has arisen during the period of such and such fully enlightened one.” In the existence of the path (maggabhave): in the existence of the noble path. Since it exists (bhavato): as it is present, as it is available.
Is he saying here that nibbāna is within every being? I find it hard to understand.
Regarding the translation, I took it from here: Full text of "A Study In Paramatthamanjusa (Subcommentary of Visuddhimagga) With Special Reference To Panna By Cha Myang Hee (OCRed) ( 581p)"