Catalysis of the reactions: deoxyamidinoproclavaminate + 2-oxoglutarate + O2 = amidinoproclavaminate + succinate + CO2 + H2O; proclavaminate + 2-oxoglutarate + O2 = dihydroclavaminate + succinate + CO2 + 2 H2O; and dihydroclavaminate + 2-oxoglutarate + O2 = clavaminate + succinate + CO2 + 2 H2O.