Eden moved to the NRL in 2015 to prove his worth Down Under but failed to feature for Brisbane Broncos under Bennett.
The 26-year-old spent the entire campaign with feeder club Wynnum Manly before returning to Castleford last year after just seven appearances.
He has enjoyed a sublime start to the current campaign after scoring eight tries in his first four matches to help the Tigers move to the top of the Super League table.
And Powell admits Bennett has recently made contact with him.
He told reporters: "I've spoken to Wayne Bennett a few times and he's always asked me how Greg Eden is going. He likes him. He's changed his mind about what he thought of him.
"His finishing has been great. He's ridiculously skilful. People always talk about the other side of him but he's not done anything much wrong with us. He's lightning quick and strong and he's a real competitor."