Bendtner, who is suffering with a nagging groin injury, has not played since May but resumed training with the squad this week, prompting speculation he could feature in the Danes' Group E opening match on Monday.
However, the 22-year-old Arsenal striker returned to the sidelines on Friday, and Olsen has conceded there is little chance of him leading the Danish attack against Holland.
"We'd love to have him back of course but I think I would be dreaming to have him back," said Olsen. "I don't think he will play."
"Surely we hope to have him back (sometime during the World Cup), he is a good player, a talented player and we hope."
Bendtner admits he is not optimistic over his chances of regaining full match-fitness in time for the clash.
"You want to be 100 per cent but you have to take it day-by-day and see what happens," said Bendtner.
"No I am not confident I will play (against the Netherlands), I will take it day-by-day then see how it works and see what happens.
"I am still missing a few things and it is not great but we will see."
Bendtner is likely to be replaced up front by Jon Dahl Tomasson for the opener if he fails to reach full fitness.