No reason to query it if there is a poa! The onus is on the giver of the poa to ensure its restrictive or all empowering and is cancelled, not on the notary to check.
He only has to ensure whatever is happening is within the remit of the poa!
Ive had a couple of completions where the lawyers of the sellers had to get the poa redone as they only had power to purchase and not to sell!
Also if the poa is done in front of the same notary as the sale then the notary hardly checks it as its his own doing!!