Hi,
as a project I simply used demo one. Steps were, create new project from example, select I2c_Ip_Example_S32K344_Q172, open mex file, update code, build and download.
If you do not have slave connected, you get no ACK, so you will see just first byte transmitted from master. Below is connection and bus signals I had
Slave disconnected

Slave connected

BR, Petr