Does my ex need a copy of my admended return in order for him to file his admendment?

You have provided no details at all.  We do not know why you amended your return, nor what your ex-spouse did.  Please explain why you and your ex-spouse are amending.  And what tax year are you amending?

Is this about who claims a dependent or are you changing your filing status?  When did you get divorced?  If you were still married on Dec 31, 2019 you can only file as Married Joint or Married filing Separate or Head of Household if you qualify.

Why are you both amending?