Confusions with placing and sizing the flyback diode, TVS and Zener
As with everything, you need to evaluate the need of the system. 

You have placed three PN devices down and each one serves a different role in their present position.

TVS
Its present location means it will only react if there is a supply over-voltage: ESD, Lightning, over-voltage. This might not be needed but is dependent on what your circuit must accommodate from a supply

Diode
Zener
One of these is required but maybe not both. The diode on its own will provide a freewheel path for the inductors current when the MOSFET is turned-off. This will produce a "zero voltage loop" and the current will decay with an exponential profile

The Zener on its own will clamp the Drain-Source potential of the FET when it is turned-off. The current in the inductor will now decay with a more linear profile, as long as there is a path via the supply. This can drive quite a high power zener as there is a need to dissipate the inductive energy in this Zener. 

Both the diode and the Zener? The Zener will not be used in such a circuit. However... there is one condition where all three are valid and that is the solenoid coil is remote from this drive channel. Under lightning conditions (automotive or aerospace), the relay harness could see large potentials. The TVS would clamp the supply rail while the zener would protect the MOSFET.

In short, evaluate what your protection needs are. As a minimum you need one PN device to manage the stored energy in the coil. Anything else is to manage safety of failure mode mitigation.  

Correct use of Flyback or Snubber diode across Motor or Transistor?

Zener Diode Selection for Relay