AITAH for breaking up with my BF ‘cause he hasn’t seen his child since April?

My bf(34M) and I (29F) have been seeing each other since last December. We began dating casually but our relationship became serious in June. He has daughter(8F) and I was quite apprehensive about dating a man with a child but he sold himself as a great present dad and I bought it.
Occasionally, I would ask after his daughter but I didn’t want to be overly enmeshed in that part of his life since our relationship is fairly new.
The issue began at the end of November when I received my niece’s (8F) Santa Wishlist which prompted me to ask my bf about his daughter’s Wishlist seeing that she was the same age as my niece. He told me he hadn’t received it and I advised him to ask for it soon or risk having all the cool stuff selling out and disappointing his daughter. He told he would.
A week or so later, I asked my bf if he would like to join me on 13 December for gift shopping especially for my niece. He declined and I asked him if he had received his daughter’s Wishlist. He told me that his daughter didn’t want a gift because her love language is quality time. I told him that I had never heard of young child refusing a Christmas gift.
This conversation quickly degenerated into an argument where he accused me of being obsessed with his daughter and insinuating that I believe that I know his daughter better than he does.
His overreaction rose some suspicions within me so I decided that I needed to reach out to his daughter’s mother – due to the length of the post, I spare the details of how I managed to get her details.
Once I found his ex’s TikTok account, I scrolled through her page and found a post with the caption “Making my daughter’s birthday extra special so she forgets that her father didn’t didn’t show up again”
I hesitated quite a bit before I sent her a DM. I introduced myself as my bf’s girlfriend and explained that I don’t mean to cause any trouble but I wanted to clarify a couple of things that I heard from my bf.
She took a couple of days to reply to my dm and she was obviously quite hesitant but she did agree to have a call with me. She asked me what my bf had told me about their relationship and I told her that my bf told me that they had dated briefly and the child was conceived accidentally. She laughed and told me that she and my bf had been in a serious relationship for 3 years and the child was very much planned. Their relationship issues began in the second trimester when my bf started questioning paternity and demanded a paternity test while she was pregnant. His ex was concerned for the safety of the child and told him that he can do the test once the baby is born. He moved out of their shared home while she was pregnant and didn’t attend the birth of his child. Once the child was born , he didn’t attend a few family court hearing to establish paternity but when he eventually did, it was proven that he was the father. Allegedly, he has been a deadbeat father since, not supporting his daughter financially or any other way and he last saw his daughter in April.
After giving it some thought, I sent a text to bf from my parents’ home where I spent Christmas in which I told him that I have decided to end based on what his ex alleges. He has been calling me nonstop, asking for the chance to talk explain his side of the story but this is too much for me. AITAH.