After jumping down in area west of nautiloid crash site to reach scuffed rock with chest, I jumped my chacters back up - and found that two of them were stuck in jump mode. One just stayed where they were, stuck in place back on top while the other followed the group around still in mid-leap position, unable to do anything but float along. Camping, teleporting etc. were not able to fix them.
Ultimately, I reverted to a prior save.
