Stoke City are one of a number of clubs who have been linked with the 20-year-old, but suggestions of a firm offer have been denied.
"We have never had a serious offer for Robin," Westroem told Fotbolldirekt.se.
"We know Robin is a skilled footballer and therefore it is natural that bigger clubs with better finances are keeping tabs on him.
"He has produced good displays here and in the national team. If the scouts have not noticed him, they have not been doing their jobs properly."
Quaison has already appeared twice for Sweden.