Salamun Alaikum,
Please allow me to provide you with a closer rendering of the Arabic in my humble opinion:
038.067-69
"Say: It is a message / news of great importance, from it which you turn away; I had no knowledge of the exalted chiefs when they were disputing"
Here a condition is captured of certain contemporaries of the Prophet who have inclined to turn away from the powerful message which has been revealed to the Prophet. It is also clear that some kind of theological questions must have arisen which prompted such an inspired response. The Quran clearly recognises a 'heavenly exalted assembly' ('mala-i-l-ala' (37:08)) who are also possibly entasked with decrees (97:4).
In verse 38:70, the Prophet clearly expresses that he has no knowledge of what may have transpired at these Divine exalted assemblies other than what he was told by way of revelation. (verse 38:70).
With reference to what the 'exalted assemblies' disputed or contended, I feel this is clearly linked to the following verses which reference some of the contentions with regards the creation of man. (This can be read in the following verses 38:71-85). This dispute can also be read in (2:30-34, 7:11-18, 15:28-43, 17:61-65 and 18:50). However, God enforces His will repeatedly and without fail as supreme authority which was picked up by the preceding verse (38:66).
I hope this helps.
Joseph