why don't you swop valve first? i told you it's no relation between your problem and TIC board. the temp sensor on TIC board is more senstive , we can trust it.
as you mention that all inks have this problem ,i am thinking about chiller may have some problem ,you need to check the water pump outlet pressure and water graded filter pressure, the chiller work condition etc.
and,you need to verfity that the image oil cooling rate is good or not , it indicate us two things,one is the oil filter,another is chiller work condition .if the oil filter is blocking too much,the image oil can not be cooling down as normal, so the image oil in oil tank will warming up fast when you print something.but even so , it still can not help us to troubleshot your problem , because the image oil can not affert ink temp too much.
ok,let's go back to another things about image oil cooling down,the chiller work condition,if the chiller work condition is bad ,you will not only see ink temp problem but also image oil cooling problem .so that's the reason i want you to verfity the image oil cooling rate . as your unknown chiller model , i can't give you further suggestion about chiller but clean condenser.
in addtion , the cyan ink's temp is more higher than other inks because the cyan BID is nearest BID to ITM.