Try this (assuming *nix as OS):

$ mv /usr/bin/perl /usr/bin/perl.real
$ cat > /usr/bin/perl
#!/bin/sh 
PROG=$1
/usr/bin/perl.real -MO=Deparse $PROG
^D
$ chmod 755 /usr/bin/perl
[download]

$ is prompt. Ctrl+D to finish entering your perl substitute shell script.

Try running your exe and it should/may (untested) spew source.

$ some.exe > source.txt 2>&1
[download]

$ rm -f /usr/bin/perl
$ mv /usr/bin/perl.real /usr/bin/perl
[download]

All care, no responsibility.