A scenario does exist where the uncertainty of Demko's reliability/longevity/cost has the Canucks seriously considering moving forward with Lankinen.
The only way I see it not being a serious consideration is if Demko comes back as a vezina caliber goalie AND has proven to the medical staff that his unprecedented condition is squarely in the rearview mirror.
The difference in cap between the two goalies moving forward -- under most scenarios -- is likely to be several million, IMO upwards of $5M or more. With the OEL penalty increasing the difference in play between the two has to be significant enough to justify a likely huge disparity between their prospective salaries.
All that said, Lankinen needs to continue to show what he has. His pedigree suggests his play is not an anomaly.