A Russian woman I know has been told by her travel agency in Russia that she MUST have evidence of a booked hotel (in this case, in Thailand) before she will be allowed to depart Russia on a holiday. She will be staying with me, and I have a hotel already booked. She has tickets, valid passport of course.
No, this is an absurd statement, since that would be a direct violation of the article 27 of the Constitution of the Russian Federation.
No, that is not correct. Only a valid passport is required to leave Russia, en route to any country. At check in, the airline would check whether a visa is required, but that is not the case for a Russian citizen to enter Thailand.