VLOOKUP and INDIRECT Formula assistance needed

shade206 

First, name list of the sheets as sheets (or whatever name your prefer)

Second, correct column number in your latest version of VLOOKUP(), it shall be on one more in each formula.

Third, make branches for the selection from drop-down list, one for ALL and another one for any other name

IF($D$6="All",<sum on all sheets>, VLOOKUP as before)

Next, adjust for your ranges formula from the link and combine all together. In F10 it'll be

=IFERROR(
   IF($D$6="All",
      SUMPRODUCT(
         SUMIF(
            INDIRECT("'"&sheets&"'!"&"$B$2:$B$10"),
            $E10,
            INDIRECT("'"&sheets&"'!"&"$C$2:$C$10")
         )
      ),
      VLOOKUP(
         $E10,
         INDIRECT("'"&$D$6&"'!$B$1:$f$11"),2,FALSE
      )
   ),
   "Day Not Worked"
)

 similar for next columns and drag first row to the bottom.

Additionally, I'd suggest to take day of the week from the date to avoid extra errors