According to Mahābhārata, did Bhīṣma ever marry or not?

Question

In a discourse on Mahābhārata today, I heard that, in the entire Mahābhārata, Vyāsa doesn't say one way or the other if Bhīṣma ever married or remained single. The speaker, Sāmavedam Ṣaṇmukha Śarma, in the video (Telugu) says Vyāsa has remained silent on the topic so it's possible that Bhīṣma married but chose not to have kids to keep up his promise made to Satyavati's adopted father.

From here, this is Bhīṣma's actual promise:

'Chief of fishermen, thou best of men, listen to what I say in the presence of these assembled kings. Ye kings, I have already relinquished my right to the throne, I shall now settle the matter of my children. O fisherman, from this day I adopt the vow of Brahmacharya (study and meditation in celibacy). If I die sonless, I shall yet attain to regions of perennial bliss in heaven!'

Above, Bhīṣma doesn't say if he's already married or not. He just says he won't have children hinting that he's currently married.

So according to Mahābhārata, did Bhīṣma ever marry or not?

If he didn't, are there any ślokas (or theirs translations) that conclusively say Bhīṣma did not marry?

_{PS. Please don't answer citing Harivaṃśa, Bhāgavata and other Purāṇas.}

Answer 1

Okay let's walk through this in chronological order.

Source: BOOK 1 of the BORI Critical Edition of the Mahabharata as translated by Bibek Debroy.

The vasus replied, “O revered one who dwells in the three worlds! You must hurl your sons into the water as soon as they are born, so that we are quickly freed and don’t suffer for a long time.” Ganga said, “I will do what you wish. But so that my union with him is not completely fruitless, let one son remain with him.” The vasus replied, “Each one of us will offer one-eighth of our respective energies. From that, a son will be born to you and will live according to your desires. But he will have no children on earth. Therefore, this valorous son of yours will remain without a son.”

Okay this is is the part where the vasus ask Ganga to have the kids. It is clearly stated that Bhishm is not allowed to have a son. Daughters aren't mentioned because they had no value during this time.

Let's skip right to Bhishma's vow:

"The son who will be born from her will be the king.”

Here, Bhishma states to Satyavati's father, unequivocally, that Satyavati's son with Shantanu will be the King.

The fisherman replies that his oath isn't good enough. He's worried because Bhishma is...well Bhishma. He is renowned within Hastinapur.

"But I do have great doubts about the sons who will be born to you.”

And here we come to the VOW. Bhishma replied:

O fisherman! From today, I take the vow of brahmacharya. Even if I die without a son, I will attain the eternal world of heaven.”

Hope that helps.