Preserve table formatting in epub?

Question

I have a latex table defined with array and tabularx, see code below.

In the PDF, it looks fine:

When I convert it to epub, it gets completely mangled:

Do I have any hope of fixing that, or should I abandon epub? I am currently thinking I should probably just distribute the PDF itself, to be sure it looks okay. However, it would be nice if it could be read on e-readers.

Making epub out of latex is hard. I ended up using this workflow:

latexml --dest tmp/book.xml main.tex
latexmlpost  -dest=tmp/book.html tmp/book.xml
ebook-convert tmp/book.html tmp/book.epub --language en --no-default-epub-cover

---

Beginning of latex table code:

% centered X for tabularx
% see https://tex.stackexchange.com/a/89932
\newcolumntype{Y}{>{\centering\arraybackslash}X}
\newcommand{\tx}{{\tt X}}
\newcommand{\ty}{{\tt Y}}
[
% two rows of five tables each:
\begin{array}{c}
%%%%% FIRST ROW
% five position tables:
\begin{array}{cccc}
% position table 1 (table and caption):
\begin{array}{c}
\begin{tabularx}{50pt}{|Y|Y|Y|Y|}
\hline
\tx &   &   & \ \hline
\ty & \ty & \tx & \ \hline
  &   &   & \ \hline
  &   &   & \ \hline
\end{tabularx} \
\textrm{position 1}
\end{array}
% position table 2 (table and caption):
\begin{array}{c}
\begin{tabularx}{50pt}{|Y|Y|Y|Y|}
\hline
\tx &   &   & \ \hline
  &   & \tx & \ \hline
\ty & \ty & \ty & \ty \ \hline
  &   &   & \ \hline
\end{tabularx} \
\textrm{position 2}
\end{array}
% position table 3 (table and caption):
\begin{array}{c}
\begin{tabularx}{50pt}{|Y|Y|Y|Y|}
\hline
\tx &   &   & \ \hline
  &   &   & \tx \ \hline
  &   &   & \ \hline
  &   &   &   \ \hline
\end{tabularx} \
\textrm{position 3}
\end{array}
% position table 4 (table and caption):
\begin{array}{c}
\begin{tabularx}{50pt}{|Y|Y|Y|Y|}
\hline
\tx &   &   & \ \hline
  &   &   & \tx \ \hline
\ty & \tx &   & \ \hline
  &   &   &   \ \hline
\end{tabularx} \
\textrm{position 4}
\end{array}
% position table 4 (table and caption):
\begin{array}{c}
\begin{tabularx}{50pt}{|Y|Y|Y|Y|}
\hline
\tx &   &   & \ \hline
  &   &   & \tx \ \hline
  & \tx &   & \ \hline
\ty & \ty & \ty & \ty \ \hline
\end{tabularx} \
\textrm{position 5}
\end{array}
\end{array}
\
\
%%%%% SECOND ROW
% ...