Just a small thought that if Diane hadn’t told her indirectly that she was related to Bojack, she never would have ended up in the hospital. Or would she maybe have pursued him anyway just to find out? She and Todd don’t really interact after that, do you think that she harbors any ill feelings about him lying?
No, he wouldn’t have. And Hollyhock had a right to know who her biological parents were. Even though it was well-intended on Todd’s end (though was a product of his own negative feelings he harbored for Bojack at the time), it was unfair of him to try to keep this from her, especially knowing it would make the prospect of finding her biological mom much harder.