Describe the bug

I am unsure what the cause is. I am solvating organometallic clusters (containing a counterion) with water, and all other counterion cases work as expected. Only Cl- causes this issue.

It appears to generate the cluster as expected, but curiously for the final cluster in grow.xyz the first carbon atom is replaced with Xx. I have used the exact inputs for many different molecules and metals without counterions with no issue, and other counterions are no issue. Replacing "Xx" with "C" results in a reasonable structure (I am sure I could make --grow and --ensemble separate CREST calls with a bash step replacing "Xx" with "C" between).

I do not think it is a memory issue as many of the counterions are much larger, i.e. those runs have more added electrons. Cl is the most charge-dense/electronegative of the added counterions, but I can't see how that'd lead to the spurious element name change.

To Reproduce
This is CREST 2.12. I am unable to share the .xyz due to IP concerns. The CREST output looks normal until the MTD runs during --ensemble, which fail (obviously due to the missing atom).

Expected behavior
No element name swapping at the end of QCG's --grow.