You will need to edit EndNote's RefMan (RIS) Export filter to export the full names in your database instead of truncating to initials.
From the "File" menu in EndNote, select "Output Style", then "Open Style Manager"
Scroll through the alphabetical list of style names, click once on "RefMan (RIS)" to highlight it, put a check in the left-hand box, then click on the "Edit" button.
On the Bibliography folder, select Author Names, then under Name Format, change the "Initials" option to "Full Names"
Close both style manager windows and when prompted to save changes click "yes"
Answers
You will need to edit EndNote
You will need to edit EndNote's RefMan (RIS) Export filter to export the full names in your database instead of truncating to initials.