EMY is the bus transfer point for both the CZ and the CCs. Unfortunately, Amtrak does not show any other bus options for the CZ. Since this is a guaranteed connection, the bus will wait for the CZ to arrive.
However, there are several CC bus connections (5) after the scheduled arrival time of the CZ, so you should be able to hop any of those. Depending upon the load, you may be able to get your bus to wait for bags to come available, should you choose to check bags (just don't tell them when making the rez).