Unable to use enconv to convert from UCS-2/LF/21..UTF-8

[contentfree]

I have a file that enca (correctly) reports as UCS-2/LF/21 (a data file downloaded from Tableau). However, enca is unable to convert it to UTF-8:

➜ enca --version
enca 1.19

Features: -librecode-interface +iconv-interface +external-converter +language-detection +locale-alias +target-charset-auto +ENCAOPT
➜ enconv -L none -x utf8 -E $(which iconv) -V data.csv
enconv: converting `data.csv': UCS-2/LF/21..UTF-8
enconv: no converter is able/allowed to perform conversion UCS-2/LF/21..UTF-8 on file `data.csv'

It seems like I need to use the output of the -i switch but that only prints out the iconv name. How do I get enca to use the iconv name when attempting conversion?