Not sure. What OS and Premiere version?
Can Premiere export anything, such as a different one-clip timeline in a different project?
If not, then perhaps it’s not a sequence/project/media issue. If it can, then perhaps it is. Did you try the following?
1. Create a new sequence. Copy the clips from old sequence into new.. Delete half the clips until you have successfully exported. (Corrupt media file finding routine)
2. Start a new project. Import that old project into your new. Create a new blank sequence. Copy the clips from old sequence and paste into new. (Corrupt project/sequence fix)