The XRP Ledger Consensus Protocol is a Byzantine fault-tolerant algorithm that enables the XRP Ledger to reach agreement on which transactions to apply, supporting millions of transactions daily. While the protocol is correct by design, its practical implementation is vulnerable to concurrency-related bugs triggered by nondeterministic message delivery between distributed validator nodes. These bugs are subtle and difficult to expose through conventional testing. In this paper, we investigate the use of evolutionary concurrency testing combined with a priority-based message scheduling strategy to explore different message interleavings. Specifically, we evaluate multiple fitness functions and assess their ability to guide the search toward buggy executions. Our results show that EvoPriority, which applies evolutionary testing to priority-based schedules, is difficult to guide toward buggy executions regardless of the fitness function used. Although it is capable of uncovering violations on a bug-seeded versions of the XRP Ledger Consensus Protocol, its performance is similar to randomized concurrency testing.