Master Eight and Master Five's reputation had been at its height about thirty years ago. At the time, Master Five had not taken his disciples into hiding yet, and Master Eight had not purposely allowed himself to get caught every few days to go to jail to teach his own disciple.
Theoretically speaking, the two of them back then had been from the same line of work, running in the same circles, and they had been able to get anything they wanted. Thus, there should have been plenty of chance for them to interact with each other, but the reality was that there had not even been one chance for them to meet up officially.
Other than the great factor of the inconvenience of the traffic situation in China back then, the other key reason was due to them not being of the same discipline.