Such kind of question are more about queue data type and general AMQP concept.
In AMQP (and in RabbitMQ, which is AMQP-compatible broker) queues are typical FIFO queues. Queue is not that type of data types that normally used for arbitrary items access and RabbitMQ at this time doesn't provide any way to bypass FIFO concept and allow such kind of access. At least out of the box. There are might be any third-party plugins, but I'm not aware of any such of a kind. And once again, it will ruin whole FIFO concept and it just become some new redis or whatever, not even talking about performance impact (one can check complexity of common data structures operation, even this Q&A on SO - What are the time complexities of various data structures? gives brief idea why adding arbitrary access is not a goal of AMQP or any AMQP-compatible broker that cares about performance).
Most of questions about arbitrary queue access comes when queues are put into wrong context: it might be a case when queue concept just doesn't fit current or desire architecture and when some key-value storage or database fist better.