Here's the latest pass at my (WIP) challenge submission.
Using this as an opportunity to get more familiar with constructing Unreal, I borrowed technique liberally from Sirhaian'Arts excellent breakdown on his Disintegration video.
Then I just created a point attractor to pull the particles into a sphere shape at the destination mesh. If I get more time to work on this, I plan to implement some way of using a (dynamic) target mesh, and to have its edges/faces attract the particles.
Cheers! Thanks for any feedback.
Edit: Switched imbed to just a Vimeo link