Agree with Walter. The dark fish is definitely a damselfish, which as he says are no more than 5 inches long, so you are way overestimating the size of the lobster. The yellowish fish appear to be longnose butterflyfish, which also aren't huge fish and also indicate the lobster is not a giant. This is probably the common lobster found in Hawaii, although the legs and antennae of those in your photo are darker than usual.