So Ainge traded 1 FRP for 3 FRPs
If Kessler is worth "two" FRPs then surely a Laker unprotected FRP is worth Kessler. This suggests to me Rob never offered this or hasn't pulled the trigger.
In 2022:
NBA Executive Believes Lakers’ 2027 & 2029 First-Round Picks Are ‘Most Powerful’ In League