David, this is super! With a single suggestion and one exception.
Before I continue, I have no doubt your friend will see this and recognise the dogs. So, what I'm about to say doesn't count - well, not much.
First, consider adding key highlights to the eyes. There aren't any in the reference, but don't let that stop you.
They make a world of difference. I once received an email from a photographer who said he'd been painting out the "pesky highlights" in every portrait he'd ever worked on... and now regretted it, having read my book. They are a natural and very useful occurrence.
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Theoretically, they shouldn't be present - especially in the right-hand dog - because the top curves of the eyeballs are at least partially hidden by the protruding top eyelids. But, as I said, don't let that stop you!
I've given the left-hand dog's left-hand eye a pure white highlight and a secondary reflection across the top of the eyeball. Then added another highlight in its right-hand eye, which I dulled down. The brilliance of the first draws you to the dog and ADDS LIFE. The second just adds balance.
Then I did the same for the right-hand dog, but dulled them even more, and reduced them in size. Possibly this dog doesn't need them, but I'd still try to include at least a hint. You do, however, have to be careful with the positioning, or you might make the dogs look up instead of straight ahead. All that said, I wouldn't attempt to add them now (especially as it's fixed). Just bear it in mind for future drawings.
The exception is the two noses. I'm certain you drew what you thought you were seeing, rather than first working out what they really looked like. BUT both are
acceptable - in that your friend simply isn't going to notice anything wrong. But both are misshapen. The left-hand dog is close to reality, but not the right-hand dog. If you're not sure about something in a reference, look online and find something similar and more detailed that you can study.
Talking of the right-hand dog... I mentioned that the "gasping fish" mouth troubled me. But it is true to that dog, and I think you've handled it very well. It's present but by no means dominant.
As for everything else... super! They have hair I could push my fingers into, and that grows in realistic layers. That said, don't get carried away with detail - you could have gently softened the left-hand dog with distance. That would throw more prominence on its head. Otherwise, the feet, the claws, the tongue, are all looking good. The wood looks realistic too.
If you aren't thoroughly pleased with this... you should be!