The vessel, docked at Damietta port, resumed unloading on Tuesday after a second sample was taken on Monday, the sources said.
The reason for the initial rejection was unclear but two trade sources cited a problem with test weight and falling numbers.
In March, Egypt rejected a shipment of Romanian wheat over its falling numbers, the internationally standardised and most popular method for determining sprout damage and so the milling quality of wheat.
A failure of the first testing process is not a rejection of the vessel as a final decision only occurs after the second and sometimes third test of the grain takes place.
Egypt rattled the global market in 2016 when it reinstated a ban on even trace levels of ergot, a common grain fungus that can cause hallucinations but is considered harmless at minor levels.