Also, the Sudetenland was key to the defense of Czechoslovakia, once it was given away, they had no viable defense against Germany.
This is also the Daily Mail so they can be rather liberal with the truth with regularity. And they love stirring the Russian hate in the UK as well after the nerve gas thingy.
The president has a busy schedule with a Supreme Court Justice nomination pending and a very important House election coming up. Vlad will have to wait his turn.