There's a few answers here worth noting because, it might shock you, but in a setting as old as forgotten realms, there are actually some answers here.
Ok first of all, the scrolls are more a player aide then anything, no revivify spell exists in D&D. now resurection spells exist, but they're EXPENSIVE. (as in the material components to cast them are pricy)
A ressurection spell is a 7th level spell (meaning you'd need a 13th level Cleric the nearest one of which is proably baldur's gate) and a true ressurection spell (which could easily be ruled to be nesscary to removing "lingering magical curse effects") costs 25,0000 gold. In addition the soul must be willing to come back, what if the only cleric avaliable is a cleric of selune? think Shadowhearts going to jump to return if she hears that "A cleric of selune wishes to return you to the Material plane"? there are a LOT of other factions. suffice to say "ohh just kill our chars and ressurect them" has a LOT of flaws.
Revivify does exist. It's a third level spell available to all level five clerics. Costs 100 gold, less than what [spoiler character] demands. Having immediate access to the spell is a plausibly non-canon player contrivance, yes, but the other means of resurrection (including the NPC) are not.
This could be a bit of a stretch, but if a character planned on dying and being brought back, or just happened to die but there were allies nearby who both intended to and had the means to bring them back, then this is information that would be available to the tadpole. Thus, it would choose to sit tight.
Resurrection in the FR setting is a difficult contrivance to build a narrative around, though.
This seems to be the most valid counterargument to me, thus far. The tadpole, presumably, has access to your memories and senses, and it could just not leave if it knew you planned on getting revived.
