The lizard scent certainly would transfer to the pinky. It's just that it is very likely that alterna(and all snakes) can still smell the pinky. No amount of washing will remove the smell of pinky from a pinky and no amount of scenting will completely mask the smell of the pinky. All that is being attempted is for enough lizard scent to be on the pinky so as to briefly suprise the alterna and thus trigger a strike.
It's a totally individual thing, some alterna will be tricked fairly easy. Perhaps just any smell of lizard in the vicinity would cause some to strike at the first thing that moves. Others will stare at or "stalk" the pink for hours before stiking. Others will never take a scented pink and will only take a real lizard. Some will not even take live lizards. Sometimes a change in caging will cause one that would not even take live lizards before, to take pinks right away. Some will take pinks scented with one kind of lizard but not take pinks scented with another kind of lizard.
As far as parasite transmission, yes it can happen. Probably the safest thing to do is scent with a frozen lizard. Even this may allow for bacterial transmission as bacteria is not the same thing as parasites and bacteria are not killed by freezing. Freezing only stops bacteria from multiplying. As soon as bacteria thaw out they begin to multiply again.
But with all that it is very rare for an alterna to get sick just from eating a pinky that was scented with a frozen lizard. In fact I don't know of any for sure cases where this is known to have happened, although I would not be suprised if it did occassionally and people just don't know it.
Personally I just get tired pretty quickly of trying to trick them and usually just pinky pump them with Fancy Feast catfood until they take a live, unscented pinky on their own. I use Fancy Feast specifically because it is finely ground and I have found sharp bone chips in other brands. I use either Beef and Liver Feast or Chicken and Liver Feast. Make sure it says "Feast" because that is the ground one, you don't want chunky style.
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