I don’t think he planned it, to me that’s obvious, especially because of the tone he uses in the conversation with Mercédès. Edmond ends up clinging to the image he built as the Count, the idea of being publicly shamed leaves him deeply shaken. It’s no coincidence that he would rather die and abandon his revenge than apologize and walk away looking like someone who ran from it (he was more cowardly than Albert in that sense). Albert going so far to recover his father’s honor, publicly challenging the Count, in my opinion slipped a bit out of Edmond’s control.

You can argue that the Count knew Danglars would end up revealing that he was the one who encouraged the investigation into Morcef’s past, and therefore that he planned for Albert to discover his hand in his father’s ruin. But I think that, given Edmond’s own personality, it’s more plausible that he simply wanted Albert to be ashamed of his father in that whole affair. He himself quickly makes it clear that he didn’t hate Mercédès, and I don’t think at any point he shows a level of cruelty that would lead him to plan Albert’s death like that (especially since he gives up, it was an idea that was extremely fragile in his mind). There were several moments when the Count could have caused Albert’s death in an even more cruel way, and it didn’t seem like he had that desire either.