Stacey, played by Lacey Turner, was last month unveiled as the person responsible for Archie Mitchell's death, bringing a long-running murder mystery to a close.
Croasdell had already bowed out from the BBC soap when Stacey's confession to father-in-law Max aired on the programme's live episode on February 19. His character Dr Al Jenkins had been involved in Stacey's bipolar storyline last year.
Asked in an interview with DS whether he is still watching EastEnders, Croasdell replied: "Unfortunately I haven't had much time for it. I believe the live episode was great and the ratings were off the chart, so I was very happy to hear that.
"It was Stacey that killed Archie, right? Wow. Well, you know I tried an intervention as Dr Al. Maybe people should have listened to me! Something to think about!"
He added: "I had no idea who the killer was going to be! Lacey Turner is such a great actress, so I'm sure they will create incredible storylines out of that for her.
"She's had a great run and I feel like she's going to win even more awards now because they are going to be focused on her very strongly, so good for her."
Croasdell recently landed a guest role on US drama Supernatural.
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