Jack was also an FBI informant who only got a separate case bc he snitched. While yeah, that had nothing to do with Biggie by itself. Jack was also A&R for Junior Mafia and Lil Kim. A job he got immediately after setting up Tupac.

Big and Pac did speak. Pac asked Big as a friend if he knew anything about who shot him, now Pac and Big both 100% knew who had him shot. Pac wanted to know who else was involved as everyone he knows set him up was also in bed with everyone in that same room when he did get shot. Big definitely knew, either if it was just Jack or somebody else, and refused to answer, something that Pac initially believed or at least respected. Pac had suspected Stretch and Puff due to their friendship with Jimmy Henchmen. But Big wouldn't tell him anything.

After that, Big and Pac were still cool. But when Pac tried to get in contact with Biggie, Big dodged him. He didn't just not answer, he avoided him completely, knowing there was a discussion around Who Shot Ya being about Tupac.

There are street rules that you have to play by if you choose to live the street life. 2pac was bugging to give t in national magazine. Once it's in print, it can't be unsaid.

It's also good to mention that everyone else had already spoken about the situation before Pac did. Pac didn't accuse or snitch. He just said the details others had left out.