Puppy food dilemma trying to switch to kibble from wet

So I have my little man Quincey that’s an absolute amazing English Cocker Spaniel puppy. So loving. Couldn’t do wrong in his eyes.

When I first got him he wasn’t eating his purina pro plan at all. The breeder even mentioned it to me that the past week before getting him he didn’t really want it.

So fast forward 5 weeks and I have a wonderfully healthy puppy that’s just over 4 months old. I’ve been mixing up all kinds of foods here and there to see what he’d like. I’ve gotten the best response on dry kibble of Diamond Naturals puppy. He still wasn’t eating much so I’d put one of those 3.5oz pedigree toppers on it and mix it up. If I did that he’d mow it down. Now I’m at the point I’m giving him Amazon Basics canned puppy food and mixing that with the Diamond Naturals. Sometimes I just give him the full can with no kibble. He also gets other cans of beef chunks in gravy, just depends what’s available. The ingredient lists on the back seem pretty positive.

The problem is I’d like to get him on pure dry kibble. 1) I don’t want to spend an arm and a leg of canned foods for no reason and 2) don’t want to dry kibble to go bad from sitting around so long while he eats half as much as he normally would. My dilemma is the “he’ll eat when he’s hungry enough”. He can stare at the dry food all day or act completely not hungry but then I’ll toss an open can out and he eats the whole thing. I just ran him a few miles and played fetch a lot and don’t want to starve him trying to be hard headed and getting him to go dry. I know the dry also packs a lot more nutrient wise into it and I want him to get everything he needs as he’s developing.

Should I just keep doing what I’m doing for a few months till he’s somewhat done with the growth stage? I don’t want him being malnourished during this important phase.