Leave it alone! It'll be fine.

I have to agree with tommyr. I live in Australia and my droseras regularily have dust and organic matter blown on them. You shouldn't have to clean the plants unless they are dying from the debris, which is unlikely.

Yes, that happens with sundews every repotting... Next time try cupping your hand under the leaves and that will shield the leaves from contact with soil mostly (you will wipe dew off on your hand, but that is also going to happen every time). It takes a bit of experience and skill, but it can be done. Same with repotting Nepenthes without loosing the liquid from their pitchers... Sundews replace leaves so fast that you will hardly notice anything was wrong with them in a couple weeks.

But its hard to avoid massing up some leaves. Just listen to tommy and leave it alone, it will sprout new leaves in no time.