It's a series of nested formulae...
=IF(OR(NETWORKDAYS(A2,B2,$M$2:$M$6)>2,AND(MOD(A2,1)<14/24,NETWORKDAYS(A2,B2,$M$2:$M$6)=2)),"Late",
if either the number of working days is >2 or both <14:00 and 2 working days = LATE

IF(AND(MOD(A2,1)>=14/24,NETWORKDAYS(A2,B2,$M$2:$M$6)=2),"OK",
if both >14:00 and 2 working days = OK

IF(AND(MOD(A2,1)<14/24,NETWORKDAYS(A2,B2,$M$2:$M$6)=1),"OK",
if both >14:00 and 1 working days = OK

"")))
otherwise leave blank.

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