I think they would have to make it a rare drop chance, like nirncrux, as you can imagine that if it were a guaranteed drop of one or two, many players would stockpile surveys until the update launched.
During the Homestead PTS, furnishing mats DID drop at first, but not from alchemy. When players reported that bug, ZOS' response was to remove furnishing mat drops from ALL surveys, rather than add them to alchemy. I'm pretty sure they were concerned about a flood of furnishing mats at Homestead's launch if they dropped from surveys, since players would just hoard them until the update.
Now, however, I think it would be great to add them to surveys, but only a chance like nirncrux (and not have them drop from the Craglorn surveys).