It wont matter , the whole tuber will dissappear forming the new stem , and slowely replace itself over the growing season . Feed it up and double the size of the tuber .

Thanks, paracelsus! I have not ever seen evidence of mites - would the insects themselves be visible to the naked eye? So you recommend giving up and starting anew - can I do this now or should I treat for scale/mites first and then remove the new pads? How would I go about removing the pads (there are two newish large ones that seem unaffected) and re-potting them? I know you are supposed to let them callus over by leaving them un-potted in a well-circulated area for a bit, right? Thanks again!!!

i would suggest you look into PREVENTION to avoid the whole mess in the first place ... which i realize doesnt solve the problem this spring .... when i used to store bulbs .. i just threw out the bad ones ... stuff happens ... i am sure the professionals even lose a good percentage of stored stock ... when i had problems.. it usually meant i put them into storage too wet .... either the bulb... or the packing material .... sorry.. i have no clue about baking soda ... ken

Not having the label for the fungicide makes it hard to know but I'd say put it on and in the dirt close to the cutting instead. Safer bet that way.