That doesn’t currently seem to be on the list of JWST missions
Any nebula that size should be visible. A ring of debris dense enough to dim a single star 22% wouldn’t be detectable easily, but a dust cloud spanning hundreds of parsecs would be. And then you have the problem that only a tiny feaction of the stars in that region are dipping. If it was an interstellar dust cloud, you’d think all stars on the other side of the cloud from us would be dipping.
It’s indeed a puzzle.
Here’s the source paper;
It’s not on the mission list yet. At least not that I could tell. But there are several proposals that could include studies of KIC846, e.g. MIRI Coronagraphic Imaging of Exoplanets.
The second paragraph of the JWST GTO Observation Specifications page says:
This page summarizes the science proposals submitted by the GTOs in February 2018. The descriptions will be updated to reflect any modifications in the revised proposals. (Bolding not mine). So it looks like this list isn’t static… Looking forward to what JWST shows us.
Chronos seems intent on pushing this idea for Big Dust.