Its only a guess, but I believe China (correctly) sees Sullivan and Blinken as corrupt Biden lackeys, ideologues and smarmy political whores who have climbed the greasy pole of woke/DNC politics.
On the other hand, they may view Burns, who has been a career diplomat and is now head of America’s premier intelligence agency (and the real power in the USA) as a more serious figure.
Xi has the evidence on Biden & Family.
Sullivan had to go to Beijing to apologize and grovel.
If the balloon had not been spotted by civilians, it would have been just fine and Biden wouldn’t have to have had it shot down...........................