I think they would have made up if it werent for the cancer. Herb felt as though Bojack only came to see him because he felt guilty that herb would die without their relationship getting closure. Which is definitely true. But herb thinks Bojack abandoned him, and what I think is more likely is that Bojack is so used to people rejecting/mistreating him for thr most minor infractions, he assumed Herb would be the same. He thought herb wouldn’t want to be his friend because hed be angry, so he avoided him out of respect or even awkwardness. Which is honestly a fair assessment. Bojack just didn’t understand that he was sad everyone abandoned him, not because he lost his job, but even so, Bojack thought it was about the job. But I think this would have come out sooner had they met before the cancer.