Does UPDATE INDEXES work for local indexes?
From the Maintaining Partitions documentation:

You can optionally specify if local indexes are also to be exchanged (INCLUDING INDEXES clause), and if rows are to be validated for proper mapping (WITH VALIDATION clause).
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Unless you specify UPDATE INDEXES, the database marks UNUSABLE the global indexes or all global index partitions on the table whose partition is being exchanged. Global indexes or global index partitions on the table being exchanged remain invalidated.

I believe you'll need to create a matching index on table2 and use both INCLUDING INDEXES and UPDATE INDEXES (but don't have a way of testing it right now).