As has been said , survivors pick up fast once past six nodes , the smelliest plants in the room at ten days flower , sex uncertain but both are welcome.
On the left quite bushy with little stretch so far , more vigorous on the right with huge fans and possibly male , both topped at six nodes ,
Down to six solid plants now , awaiting results of soil analysis from the supplier , all senecio greyii in the same compost are dead with similar symptoms , this is a good indicator for boron defficiency.
Clones root fine in the remains of last years compost , they progress slowly and fail in this seasons so there is something in there , or lacking , that these plants are particularly intolerant of.
Can pull out a dead wavey clone and replant a different clone in the same compost without any problems , they grow away as normal.
My personal theory is that the loam soil used in its preperation has been subjected to heavy doses of glysophate , am useing the bulk mix but the same product is sold under several names in garden centres and sheds.