To help troubleshoot, find the opera binary and run the “ldd” command, for example: $ ldd /usr/bin/opera
.. and paste the result here.
Edit: Maybe this: $ ldd /usr/lib/x86_64-linux-gnu/opera/opera
Edit2: This: $ file /tmp/deb/usr/lib/x86_64-linux-gnu/opera/opera
/tmp/deb/usr/lib/x86_64-linux-gnu/opera/opera: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 3.2.0, BuildID[sha1]=fe23aa0fbe87fe3d5a3d4db168cb9cf65a6ffd7e, stripped
..shows that you will need the /lib64 -> /lib symlink