Money not points. They don't even do the upgrades themselves it seems. it's been outsourced to a company. Since no airline with an ounce of sense will allow this for less than the usual cost in miles of a business class ticket (e.g. they won't encourage passengers to use the sum of economy miles + upgrade miles that adds up to less than the regular cost in miles), for other than highest level elites, with Avianca you are barking up the wrong tree.
Call them and put the economy award back if they will reissue for more miles in business class. BTW $400 each way is not terrible and beats sitting in economy for any distance.