Nicaragua made Taiwan close down its Embassy. It can still open a trade/culture office.
The one in Lithuania is still not an embassy, but a representative office. The detail is in the syntax. Lithuania still has diplomatic relations with PRC, not ROC.
Taiwan has cultural and trade offices all over the world. China even allowed them to join the APEC as Chinese Taipei.
What Lithuania has done was like half-hearted prostitution. They still recognize one-China principle (Otherwise, no diplomatic relations are possible with the PRC), but, weirdly, renamed the Taipei office as Taiwanese office (not even 'Taiwan' office).
They simply made things unnecessarily complicated for themselves. If they really cared about ''oh ye 'tis democracy,'' they could have simply done a reverse Nicaragua.
Sometimes, my faith in evolution falters.