If it was just the foot, I'd wonder if he possibly had some foreign object in it (a splinter, or bee sting - something like that). It's worth checking anyway, to see if you can find something. But combined with a recent ear infection and bumpy skin - well, it sounds a lot like allergies.
To work this one out, you've got to do a bit of an elimination trial. First thing I'd suggest is tossing away the bully sticks and the treats. I don't put any value on bully sticks anyway, so nothing lost by eliminating those. But the steak (ie. real meat) is a bit of a sad loss - meat is a wonderful addition to a dog's diet. Nonetheless, if you're going to figure out possible food allergies, those things have to be stopped for a bit.
My suggestion would thus be to first eliminate everything except his kibble from his diet. If the symptoms dissipate, incidentally - you've proven that it was caused by either the bully sticks, the steak - or both. You would then add one of those back into his diet/routine and see what happens. A couple of weeks later, test the other.
But if, when he is consuming nothing but his kibble, the problem continues, you will have found 2 things: (1) the problem isn't steak or bully sticks - not beef, in other words; and (2) the problem might be his kibble.
In this case, you would then need to switch foods. The thing to do would be to change to something that contains none of the ingredients that are in his current food (something like Natural Balance's potato/duck could be a good choice) and - if possible - that has different ingredients to anything he's consumed before. If a food allergy exists, this should bring about a near-instant improvement. It can take several weeks to get total clearance of symptoms, but still, improvement should be apparent quickly. That is because he cannot have pre-existing antibodies against something he's never encountered before (an allergy being an abnormal response of the immune system, producing antibodies to fight some perceived allergen).
If that improvement happens - then you've proven that a food allergy exists to something in the Timberwolf Ocean Blue. You would then have the joy of adding things back into his diet one by one to discover the exact culprit(s). It is very much worth knowing what exactly the problem was - so that you know what to avoid in the future.
If no improvement occurs with a unique food though - then you've fairly well proven that it is NOT a food allergy at all. In that case, you're looking at finding environmental issues. That can be a long process, and a bit hit-and-miss (like people, dogs can be allergic to anything at all - grass, dust, particular detergents, etc). It's can be rather more difficult that dealing with food issues too, since it's not necessarily possible to eliminate the problem. Allergy testing, whilst far from a precise science, might be the best bet in that case. Do check the food thing first though - aside from being much easier, what you've described sounds as though food is at least as likely as environmental allergies.
