They might not have been able to reset this year. They might have had to wait one more year. It might have cost a few extra million in tax.
Or they could have traded JDM, traded Price, not signed JBJ etc. That would have offset Mookie's 27 million.
If the tax issue was the prime reason they traded Mookie, it's a horrible one.
You have made a persuasive case against giving Mookie $350-400 million. I can accept that as the one valid reason to let him go.