Download DataSubset (Cloud) - maximum limit to column header length in excel

Is there a max limit on the length of column header in the exported excel? We are exporting result to an excel using ExportableDataSubset. Our requirement is we need to generate the columns in excel dynamically from some entity names present in DB. When the column length is less, it exports the result successfully to excel. But when the column length exceeds a limit (for us, it works with anything < 100 characters), it throws error-500, and we can see from log that it reports -
"There is a fieldname mismatch between field(s) in the expression and those in the datasubset on <fieldname>"/
- Please advise.

OriginalPostID-268507