Any way to stop foliage instances from moving whenever actor they placed on top of is moved?

I need to fix pivots on my floor tiles - currently it’s bottom-centered. But Marketplace staff wants it to be bottom-corner.

Problem is - if I re-import a mesh with new pivot, I have to move around all the actors that use this mesh to fit into position correctly. That itself is not a big deal. However, I have foliage instances scattered across my scene - rubble and hay strands - that move together with the actors they were placed on top of. This results in all the foliage instances taking incorrect position, some moving behind walls and stuff.

I thought, well maybe if I just delete the old actors and put new ones in their place… But no, that also deletes foliage instances on top as well.

I know I could just delete all the floor and re-do the foliage instances again… But that seems extreme. And I’m lazy.

Is there any work around to this?