1) I was interested in creating a vanity wallet on bitaddress.org, but it points me to the vanity pool website to paste my public key and there's no field to do so. Is the vanity pool website defunct?
Yes. If you want to generate a vanity address, it is recommended that you do so yourself on your own hardware using the vanitygen software.
2) On directory.io, why do addresses and their corresponding compressed addresses show different transaction information on blockchain.info? Aren't they essentially the same address?
No, they are not the same thing. An address corresponds to the hash of a public key. The hash of an uncompressed public key will be different from a compressed public key, so there are different addresses and thus different transaction histories.