Thank you for your data.
I was checking this and it looks like the data are somehow interfering themselves. When there is only one scan, the seats looks good, but when they are aligned, there are some issues.
Was that space scanned like the example scans? I would suggest to add some additive positions, like from the ground, from the tables, under the tables.
Also, as these are Z&F scans, have you tried to import .zfs files?
Anyway, as there is this interference, I will create a bug for it.