mcexam throws "incomplete ifx" when randomizeanswers=true under Windows 7 TeXLive

Given the MWE below, Windows 7, TeX Live 2019/W32TeX and LuaTeX, Version 1.10.0 (or pdfTeX, Version 3.14159265-2.6-1.40.20 or XeTeX, Version 3.14159265-2.6-0.999991):

1. I compile properly with randomizeanswers=false
2. I compile properly with randomizeanswers=true as long as each mcanswerslist sets either ordinal or fixlast
3. I get a Incomplete ifx; all text was ignored after line 34 error with randomizeanswers=true and permuteall (either explicitly or by default)

Line 34 is the end{mcquestions} before end{document}.

documentclass{article}

usepackage[output=exam
  ,numberofversions=1
  ,version=1
  ,seed=1
  ,randomizequestions=true
  ,randomizeanswers=true
  ,writeRfile=false
  ]{mcexam}

begin{document}

begin{mcquestions}

question What is going to be on the exam
begin{mcanswerslist}[fixlast] % `fixlast` allows compilation
  answer Russell's antinomy
  answer Gödel's numbering
  answer Borges' library
  answer Smullyan's What Is The Name Of This Book
  answer[correct] all of the above
end{mcanswerslist}

question Have you ever danced with the devil in the pale moonlight?
begin{mcanswerslist}%[ordinal] % `ordinal` crashes
  answer Cesar Romero
  answer[correct] Jack Nicholson
  answer Heath Ledger
  answer Joaquin Phoenix
  answer Mark Hamill
end{mcanswerslist}

end{mcquestions}

end{document}