Hejduk would still play with one of Forsberg or Sakic. I doubt his career would be less spectacular. The difference would be that Avs would have a extremely potent RW which they lacked during that period. Deadmarsh were slowing down and Lemieux was traded for Rolston, Fleury and Hejduk would be golden.
The big difference would be being the 1st option on RW and on the 1st PP for a player like Hejduk. With Fleury there I don´t think Hejduk gets his Richard 50 goal season. Most impressive about that season is that he led the leuage with 32 EV goal. With Fleury there he would probably not get as many minutes out there when they where chasing a lead or a tying goal. And 18 out of thoose 50 where scored on the PP. Fleury would probably still be the main option, or at least give the Colorado a 2nd option to Hejduks spot (outside Forsberg and Sakic the next highest goal scoring Colorado forward was Tanguay and Vrbata with 3 each... Hejduk was not just the main trigger man, he was the only trigger man as forwards go...). That season is his defining season (along with the 01 PO.s...). With Fleury there I would guess Hejduk instead gets around 40 goals. So to me that takes away his only really spectacular season (even if he had a few other good ones...).