Finding IV in AES-128 having partial Key and plaintext
The way to solve the problem is the following:


Bruteforcing the last 2 elements of the key.
With that key, trying to decrypt the second block of the ciphertext.
XORing that result with the second block of the plaintext.
Comparing the new result with the partial first part of the ciphertext.
If there is a correspondance we have found the right key (also the complete first ciphertext block), else go to step 1.


The last step is applying XOR to the decryption of the first block of the ciphertext and the first plaintext block. This should return the IV that we are looking for.

Since there is no padding (plaintext is 32 char long) this was not too difficult after a better understanding of the algorithm.