You're in a really tough position. I know you want to be as safe as possible. I think you need to talk to your OB. Let his/her office know that you need at least a 15 minute phone call to talk this through. Like you said, we can't provide any medical advice. My suggestion is to ask your OB what the standard procedure in Canada would be. Would it be the same as the treatment you are receiving now?
In the U.S., you wouldn't be put on hospital bedrest at 30 weeks with a 2.26 cervix unless you had bleeding or leaking fluid, or very high blood pressure. They would tell you to take it easy/lay down at home and call them if you were to continue to have contractions. You would NOT be hooked up to an IV, and you wouldn't be given any shots every few hours. You might be put on a medication that helps reduce contractions, but ONLY if that is an issue. Also, you have the right to refuse the IV.
PLEASE PLEASE call your doctor. You doctor MUST tell you what s/he would do if you should up at his or her office with the same symptoms. Has s/he talked to the doctors in Greece? And received ALL test results? Is your doctor concerned about you flying? How long is the flight? Could you stay at a hotel nearby? Again, I can't provide medical advice. Only you and your doctor can decide what is best. Let me know how it goes. Sending prayers.