Thorough but there is an error, you can use the positive antibody test to get back into USVI by land or AIR. Im using it to get into the USVI by air on my way down and by ferry on my way back.

quoted from the USVI portal site front page: https://usvitravelportal.com/

Every traveler aged five or older who enters the U.S. Virgin Islands by air or sea, including anyone in-transit to another destination, is required to use the USVI Travel Screening Portal AND to submit a COVID-19 test result prior to travel.


Travelers are required to provide evidence of:


a COVID-19 molecular (e.g., RT-PCR, viral or nucleic acid amplification) test from a nasal or throat or saliva swab sample taken and NEGATIVE result received (both within five days of commencement of travel to the Territory)

OR

a COVID-19 antigen (rapid) test from a nasal or throat swab sample taken and NEGATIVE result received (both within five days of commencement of travel to the Territory)

OR

a COVID-19 antibody (rapid) finger stick or blood draw test taken and POSITIVE result received (both within four months of commencement of travel to the Territory)