that is annoying. certainly a drench with provado will kill off any other vine weevils. But it may also kill any other critters in there that aren't doing any harm. at this time of year I regularly knock out pots and check for them.

look for the adults on an evening as they go walking about feeding and laying eggs. then squish them. they cant fly so that makes it easier.

Have you checked right up inside the Heuchera stems, they do enjoy burrowing into stems. I don't usually put them in water just into fresh compost. a gritty compost also seems to limit the number of eggs laid as the grit is uncomfortable for their egg laying tube.

They are a real pest. I have yet to see this season how successful my drenching of my azaleas has been with pesticide. But the biggest hassle for me was trying to catch the beetles at night. I went out several nights in the dark with a head torch and shook the shrubs. I certainly did get some beasties, but am pretty certain I did not get them all. However, hopefully the winter will have taken care of the beasties and the drench will have sorted the grubs.

Indoors, you should find dealing with them a little easier.

Good luck!

They don't like peat based compost so use peat free.

Some may object to this, but I've used hydrogen peroxide.to save my cone flowers and it worked. The grubs came in from the garden center I bought it from, they weren't in my garden. You have to remove the plant from the pot, completely clear away all the potting soil, then submerge the entire plant in a bucket of water with hydrogen peroxide. Swish it around in the bucket for about 5 minutes. The HP will completely sanitize the plant. Then plant it in a new pot with new potting soil. Now you have to prevent re infestation.