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As other people has said, if there's no sign of life by now then the seeds were probably bad. I would still keep the pot for a while though, there is a chance the seedlings could still pop up. Last year I sowed some Turb flaviflorus and got no germination for a couple of months and figured it was worth the risk of sowing some Turb lophophoroides on top. Both species came up 2 weeks later and its fair to say that now the pot is quite full!

Yes, this week I actually sowed some mammillaria seeds on top of them.
And most of those mammillaria seeds germinated so we'll see what happens