Issue with SQL server updates, missing xprepl.dll

Question

SQL server 2019 could not normally be upgraded with any CU or Security update.

settings: SQL server 2019 with AlwaysOn and CDC.

Main steps from logs:

• Database 'master' is upgrading script 'repl_upgrade.sql' from level 251662630 to level 251662635.
• Could not load the DLL xprepl.dll, or one of the DLLs it references. Reason: 2(The system cannot find the file specified.).
• The failed batch of t-sql statements : set nocount on declare @script_status int

      ,@repl_script_key nvarchar(277)
  
      ,@repl_script_value nvarchar(8)
  
      ,@retcode int
  
      ,@repl_installed int
  

  -- this script will be run regardless of whether replication is installed -- check to see if replication is installed before proceeding execute master.dbo.xp_instance_regread N'HKEY_LOCAL_MACHINE',

                                   N'SOFTWARE\Microsoft\MSSQLServer\Replication',
  
                                   N'IsInstalled',
  
                                   @repl_installed OUTPUT,
  
                                   N'no_output'
  

  select @repl_installed = isnull(@repl_installed, 0) if @repl_installed = 0 and not exists(select * from sys.databases where is_cdc_enabled = 1) begin

  raiserror(N'Neither Replication feature is installed nor CDC is enabled. Upgrade scripts will not be run.', 10, 1)
  
  return
  

  end select @repl_script_key = N'SOFTWARE\Microsoft\MSSQLServer\Replication\Setup'

      ,@repl_script_value = N'Upgraded'
  

  -- Set script upgrade status to 0 set @script_status = 0 if @repl_installed != 0 begin

  execute @retcode = master.dbo.xp_instance_regwrite N'HKEY_LOCAL_MACHINE',
  
                                                     @repl_script_key,
  
                                                     @repl_script_value,
  
                                                     N'REG_DWORD',
  
                                                     @script_status
  

  end begin try

  raiserror(N'Executing sp_vupgrade_replication.', 10, 1)
  
  exec @retcode = sys.sp_vupgrade_replication
  
  if @retcode != 0 or @@error != 0
  
  begin
  
      set @script_status = 0
  
  end
  
  else
  
  begin
  
      set @script_status = 1
  
      raiserror(N'sp_vupgrade_replication executed successfully', 10, 1)
  
  end
  

  end try begin catch

  -- re-raise the error non-fatally
  
  declare @error_msg nvarchar(2048)
  
  select @error_msg = ERROR_MESS...
  

• Script level upgrade for database 'master' failed because upgrade step 'repl_upgrade.sql' encountered error 35262, state 4, severity 10. This is a serious error condition which might interfere with regular operation and the database will be taken offline. If the error happened during upgrade of the 'master' database, it will prevent the entire SQL Server instance from starting. Examine the previous errorlog entries for errors, take the appropriate corrective actions and re-start the database so that the script upgrade steps run to completion.
• Attempting to copy article resolvers from SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL15.MSSQLSERVER\Replication\ArticleResolver

It looks like xprepl.dll is missing but there is the exact error as on CU6 for SQL2022 (2442348).

The standard way to repair does not work.

The SQL servers are upgraded after several restarts, but all Extended Events have been recreated from scratch and lost previous data.

Anyway, it does not look normal. Any ideas how to fix it?