I realized that my host provider's copy of Linux didn't have basic commands like sudo or man (
declare -p and
help finally told me I was running some kind of zombie copy of Red Hat Linux), so I got around the entire vi fiasco by setting up the bl subdomain through my hosting provider's Plesk console and then adding a .htaccess file there. I think one of the features I enabled while creating the subdomain allowed me to add the .htaccess file, but maybe I'll never know for sure, and I'm cool with that.
After successfully doing a silent redirect from bl.argh.gr to my EC2 instance, I tried to change the favicon as well, but I'm not really sure if it's broken or if the changes haven't propagated yet. Either way, idgaf. Welcome to the blog.