Copy your if statment and then edit it so that a line like this:
if [[ $first = '*** Testing file' ]] &&
becomes like this:
Xfirst='*** Testing file'
and do that for Xsecond and Xfirst as well. Make very sure that the constant is exactly the same as in the if statement. Put the new lines in front of the if statement. And after them put 6 lines like this:
echo the length of first is ${#first}
echo the length of Xfirst is ${Xfirst}

and so on with the other 4. This will show you how long the variables are. And how long the constants are. Something has got to be off.