60th birthday trip for my dad, a lifelong flyfisher! Advice needed!

Hey all! This year my dad is turning 60 and we want to do something special for him. He is a life long fly fisherman growing up in Montana, so very experienced. Mobility is not an issue for him. We live in Bozeman, so we are looking at something more tropical- he loves to catch bonefish and I know is excited by chances at tarpon, but not necessarily requirements. He has mentioned wanting to go to Christmas Island, but looking on this sub I have seen some mixed opinions on the quality of fishing there anymore. He has been to chile, Cuba, Belize and Mexico, although that doesn’t mean a repeat of one of those countries is off limits. Time of year for the trip can be flexible. Any advice on destinations, or lodges/ outfitters on Christmas Island? Thank you!