"he waits" and "he is waiting" is the same thing... both work for the translation.
It is and is not. One strongly suggests it is happening right at this moment. And so does the word čeká. To suggest otherwise and make it a regular repetitive activity you would need to squeeze in something like "always waits" "vždy čeká" .
It is not possible to tell wether he or she is waiting so why is one of it wrong?
Both 'he' and 'she' are accepted.
"is waiting for two sweaters" wrong ?
Who is waiting? English requires a subject. He, she, it.
Why not "She is waiting on two sweaters"? I speak AmE, and that is extremely common. In the American South, you will hear this almost exclusively. Many other "incorrect" colloquialisms are excepted.
We accept this feature in most sentences. Use the repor button to report where it is missing.