Tom definitely paid attention to Veronica not just because she saved him. Damn, it took Jimmy over an hour just listening to Tom introduce Veronica's birthplace and burial site, as well as some of her personal habits. Although there were some things mixed in about the original Jimmy, most of it was still about Veronica.
If it were just gratitude, the most he would do is look out for Veronica's son, but the details of this investigation are really extensive.
If it weren't for Jimmy's sharp mind, he would have been confused long ago. Veronica's life was just too rich, and it involved confidential matters. Tom wouldn't tell Jimmy either, focusing instead on her various travels to Europe and her last few years in the United States.
