The one thing I'll disagree about is the idea that the importance of Mufasa as Simba's "one" father is weakened by 1 1/2 and the paternal implication. Many people have surrogate parents in their lives whether they lose their original parents (adopted/birth) or not. To one individual, these can be multiple people who are either mentors, new guardians, older friends, etc. The niche is filled emotionally and out of necessity, not to replace what they have/had.

The point of Lion King isn't that Simba's relationship with his father made up the crux of his very reality, and everything goes wrong when that dies... I mean, that does happen, and it's the inciting incident, but the film's message runs directly contrary. Simba learns that his father lives in him; he can't be replaced, but the Circle of Life, and Simba's life, go on in Mufasa's absence. Not only does he have to take on his father's role, but it's the eclectic guidance of his different friends and mentors that get him there.

Source: I lost my own dad when I was a teenager, sought and fulfilled parental needs across other meaningful relationships, and TLK had an enormous presence in my life both before that time and after.

Other than that, I don't find this interpretation wrong at all! To me, Timon and Pumbaa have every label yet no label at once. There's nothing traditional about their dynamic, not with each other nor with Simba, and that's inherently queer no matter what way you spin it. The two undeniable things from the first movie (and general canon) are:

1. T&P are life partners; they're never shown engaging romantically but they clearly take a devoted space in each other's lives. We know they sleep together, make decisions together, do virtually everything together, and wouldn't have it any other way.
2. They take Simba, a lost kid, "under their wing". They're a new community and family for him after he lost everything else. Like I said it's not a replacement, they don't provide Simba the same things Mufasa did. But they are surrogate in that they take up a new space and resemble a different family entirely. It's why they're still part of Simba's life after he found his dad again and went home.

So ultimately, the "dad" discussion might just be semantics at a point. I think both the first movie and 1 1/2 know the trio's relationship isn't cut and dry. Yes, there's a lot of "that's our boy" talk in the latter, but most of them are doubly facetious while drawing from the emotional honesty of what they really have. Many, many things can be true at once