That all looks pretty straightforward to script. Here's a basic idea of how it could look.

Code:
on *:text:*:#: {
  ; If you need to check the $nick, you can do so here and stick everything
  ; that follows inside that IF's brackets.  Otherwise, if the command can
  ; be used by everyone, then don't bother including the $nick check from your original code.
  if ($1 == !check) { msg $chan !pl }
  elseif ($nick == ServerBot && (Allies: == $1 || Soviets: == $1)) {
    ; Perform whatever check you need to determine if there are matches.
    ; You didn't explain how that was decided, so just put that code here.
    ; Set it to %pl.match in the format of name1 name2 name3
    if (%pl.match) {
      var %t = $numtok(%pl.match,32)
      msg $chan Found %t player $+ $iif(%t > 1,s) on watch list.  Performing Search.
      ; Note that here, depending on how you need to format the name(s) for !pi,
      ; you may have to loop through using $gettok() to run the command on every match.
      msg $chan !pi %pl.match
    }
  }
  elseif ($nick == ServerBot && ($4 == Sov || $4 == All)) {
    ; You may need to adjust the IF to a better method of determining that the text is your data.
    ; You will also need to add in whatever code you need for the script to log and notice admins.
    msg $chan Info logged and notice sent to admins.
  }
}

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