Sync White Balance (Temperature & Tint) issue

Is the white balance in the first shot "As Shot" or "Custom"?

As Shot will just synchronize to As Shot, even if the original temp/tint numbers are different.

Custom will synchronize the actual numerical values.

when I synchronize with another photo, these two values are different. In the "synchronize settings" window, I always leave all the boxes checked

So from that statement I take it you are referring to:

May I propose a  approach. For your reference photo, select that WB you want, then in the menu bar, in Settings, select Copy Settings

and select White Balance. Click on Copy

Go and select those other images, then back in the menu bar, in Settings, select Paste Settingsexcept

As a first troubleshooting step, verify that the source and destination photos are either both raw or both non-raw (e.g. JPEGs).  Don't assume they're the same type -- type "i" in Develop a couple times to see the file name overlaid in the upper-left corner.

Copying Temp and Tint from a raw to a non-raw or vice versa won't yield the same values.