Olden is located in a deep fjord with scenic cruising. For the late May you’ll miss the scenic cruising as well as Geiranger- Hellesylt is only a technical stop. Ålesund is a nice  DIY city - might be a OK substitute for Geiranger. Also as suggested by gumby-ng you can arrange a boat tour to Geiranger (if available early May). Link to a Tour provider - there might be more.