I think you're missing essential information, i.e. the salt that had been used to initialize the encryption.

There are two modes to store the salt / initialisation vector (IV) together with the data:

• OpenSSL compatible, in which case the string would begin with "Salted__"
• RandomIV mode (legacy), in which case the string would begin with "RandomIV"

As your data doesn't begin with either of those headers, it's presumably without a header (i.e., you should've been told what the salt/IV is, so you can specify it explicitly), or it's in some other unknown/incompatible header format...

(BTW, there's also a decrypt_hex() convenience method, which you could use to pass your hex data directly — once you've figured out the salt issue, that is...)