Voltage spikes with ZVS full bridge
From your waveforms, it seems that the current through M4 M8 pair (right lower MOSFETs) is not zero at the time they stop conducting. This current (and the energy related to it) excites some oscillations. It is not important where they happen; it is the non-zero current that causes problem.

You can use current transformers (ferrite rings with ~100 turns winding, the latest loaded to few Ohms resistor, the ring is placed over the high current wire) to see what currents do you have.

And my last question is: why do you expect ZVS conditions for this circuit? I did not simulate it, but it is not obvious it works in ZVS mode.