Can this little guy be saved?

[cactusgurl]

Hi all, I recently purchased a cactus which came with this young pup. There was a brown mushy spot on its side which I carefully cut out until I saw green and healthy flesh. I think the fungi might have been more advanced than I thought because it now looks like this:

I'm scared to cut out any more since it's already so small. What can be done? Thanks for reading.

[cactushobbyman]

Cut it above the rot and if there is some green left, there might be some hope. I'm thinking not, sorry.

[Aiko]

I also think this Echinocactus platyacanthus (?) is doomed.
It is easy to grow it from seeds and seeds are easily to obtain. You might like to try to grow it from seeds.

[cactusgurl]

Thank you all for the replies. It does seem he's too far gone, he's completely soft now. Thankfully I still have the parent plant.