I am not sure whether the VF will be appended or prepended to the entropy. Because you said "prepending" but the quote below looks like the input to the hash function will be ENT + VF, not VF + ENT.
A checksum is generated following the BIP39 method: taking the first (ENT + VF ) / 32 bits of the SHA256 hash of the combined entropy (initial entropy plus the 32-bit version field). This checksum is then appended to the combined entropy.
The 32-bit version field is indeed prepended to the initial entropy, I agree that
make it confusing.