Well, in an interesting turn around - the Bahamas has now closed to US tourists as of July 22, thanks to 40+ new cases of COVID after opening back for business on July 7.
Rumors for Roatan are that the airports will open in limited fashion in mid August and then fully a week after that. They are still under curfew (second extension), so not sure how viable this rumor is. The Governor of the Bay Islands did report this morning that the airport is undergoing inspection in preparation for reopening.
Also, the Cayman Islands will have a phased opening starting on September 1, which will include a negative COVID-19 test within 72 hours prior to arrival, 5 days of quarantine, and a second negative COVID-19 test. This intended to allow those who will be staying on the island long term or returning to the island for work to enter. Targeted start of the next phase (waiver of quarantine) is proposed for October 1, but as with everything, can change.