I do not think you need the TableCount variable, and perhaps a few other things inside your original code. Hopefully, this will put you on your way...

> cat script.sh
#! /bin/bash

NumberOfTables="$#"
let TableCount=1

while [ ${NumberOfTables} -gt 0 ]
do

 TableName='$'$TableCount
 
# db2 "runstats on table ${TableName} and indexes all"
# echo ${TableName}
 echo $1
 shift 

 let  TableCount=TableCount+1
 let  NumberOfTables=NumberOfTables-1

done
exit 0

> script.sh table1 table2 table3 table1 table2 table3