Good catch. The codes of bigcap and bigcup are mixed up.
For a quick fix, open the file direct.cfg in the cfg folder of the latex2rtf installation with a text editor and change line 40
\bigcap,{\u8899}.
to
\bigcap,{\u8898}.
and line 42
\bigcup,{\u8898}.
to
\bigcup,{\u8899}.
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Good catch. The codes of bigcap and bigcup are mixed up.
For a quick fix, open the file direct.cfg in the cfg folder of the latex2rtf installation with a text editor and change line 40
\bigcap,{\u8899}.
to
\bigcap,{\u8898}.
and line 42
\bigcup,{\u8898}.
to
\bigcup,{\u8899}.