Are the cameras being recorded live to a computer via an Video Switcher/NLE or to media in the cameras for later editing?
If in computer, are you using a software or hardware video switcher for recording this job? Monitor windows on the computer can show all cameras depending how it is setup.
Software examples (Vmix, VidBlaster, Wirecast).
Hardware example (Tricaster, or look at these https://www.bhphotovideo.com/c/buy/Live-Switcher/ci/2865/N/4028759398 )
pxw z150 cams have WiFi broadcasting of live video feeds, so you can log in and watch on a computer or phone or tablet over WiFi. Should work without an internet connection, but a WiFi router set up for local networking.
Check out your manual or https://www.bhphotovideo.com/c/product/1222976-REG/sony_pxw_z150_4k_xdcam_c...
Ways to stream to a single monitor system.
(No additional cost) On a computer you should be able to view more then one camera on screen live by opening two browser windows.
(Cost is minimal) There are applications or Apps for viewing IP webcams that would work. Computers, Tablets and Phones.
(Can be Expensive) Use a software video switcher using the WiFi streams from the cameras on a computer screen.
(Most Expensive) Use a hardware video switcher usually requires a wired connection but may work using WiFi streams.