Check the Data- and Catalog-Protection for all your Configs. The Full-Backup should be set to a longer Protection as the Incrementals. Make sure you set up proper Logging-Levels on all Jobs, If your Full-Job runs with NoLog you won't get lucky.
Also you didn't specify if the latest Full-Backup is still imported or already in the Vault, in last case the Catalog would be usually removed from IDB, hence the missing browsability.
Maybe try "omnidb -winfs Host:MountPoint Label -session SessionID -catalog" to get a list of all Objects that were locked in the Full and Incr Sessions.