Iketara iku (行けたら行く): I will go if I can. In 2020, the columnist Fukazume quoted a reader from the Kansai region in the women’s weekly Josei Seven: Kotchi de wa “iketara iku” wa kesseki no imi desu. Hontō ni kitara bikkuri shimasu. “Here, ‘I’ll go if I can’ means absence. If someone really comes, we are surprised.”
A 2023 etiquette article on Mynavi News advises against such vague answers. A person who wants to decline, it says, makes a better impression by declining clearly.