Why is that suspicious? (I don't know this Rabbi and I agree that you always have to do research)
I don't know what
@aygart had in mind, but IMHO - large scale programs in resorts and hotels are notoriously difficult to supervise and ensure everything is up to standard. There are numerous highly professional, well-run hashgachos that won't go near certifying programs because of the difficulties involved. It is therefore suspicious that a Rabbi that doesn't usually provide even regular hashgacha would take on that responsibility. Even with the best intentions, there are simply many things that can go wrong without a massive level of planning and protocols put in place. It is possible, but something which needs an extra level of research. Additionally, why is the program opting for an unknown entity and not using a recognizable, renowned symbol? Again, it's not necessarily an issue, but just something to look a little deeper.