If you find the job, I’d suggest putting it on E-Bay there are tens of thousands of people all over Europe that will have bought a ticket to Malaga this yr in the hope of finding that job.
Yes Spanish is not essential, but unless you want to join the 4 Million + currently unemployed in Spain I would recommend you learnt some.
Also imagine if your walking down Malaga high street and you suddenly feel ill and you need medical help, how you gonna communicate to the ambulance crew, assuming ofcourse the operator understood you and your description of your location before you drop dead.
I once called to a guy who at the same time was on the phone to the car recovery guys, his car had broken down in the countryside he called them when it happened, they didn’t understand him, so he left the car in the hope of having a friend help him tow it home, but when they arrived someone over night had removed his alloys and brake discs, shocks and a few other bits, so he had to re ring the recovery guys, just when I arrived, luckily for him I was able to translate and give directions and get a time for him to meet the recovery truck, other wise his car would have been stripped.
So yes you can get by without Spanish, but only if your lucky.