I am no expert but as I gathered some information about the 433 Mhz exec binding I found something.
The tutorial shows the solution with exec 1.8 or 1.9 under openhab (the old one). The new openhab works with exec binding version 2.0 and the solution from the tutorial doesnt work anymore. Here are some links about workarounds but I couldn’t make mine work.
If you have an arduino i will try first to capture the signal protocol and pulselength with the receivedemo example given with the rcswitch library. After you can try to reproduce it with a send example still with an arduino. If you succeed take these parameters and try to reproduce it with the pi.