Crap, I had this elaborate reply typed out covering everything you mentioned but accidentally hit back and lost it.
But yes, I can confirm that there are at least 3 known instances that are currently broken when trying to infect a root node.
The bots sadly didn't get prioritized in the end, so they never learned how to to infect.
And the win screen was very anti-climatic, so you're not missing out on anything xD ( "Player X won!" replacing the label used for "Player X's turn")
Thanks for taking the time to play our game and leaving a comment! I'm excited to go back and take my time to rewrite everything from the ground up to support all the systems I had in mind and see how it plays.
To clarify for other readers, there are no "abilities" other than being able to infect your target and then using your target's infected branches to delete branches of their target (in lieu of trying to maintain a branch infecting a branch, infecting another branch).