On a curious equation regarding odd perfect numbers

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Let $p^k m^2$ be an odd perfect number (OPN) with special prime $p$ satisfying $p \equiv k \equiv 1 \pmod 4$ and $\gcd(p,m)=1$.

Since $\gcd(p^k, \sigma(p^k))=1$, then we essentially get the equation $$\frac{\sigma(m^2)}{p^k}=\frac{D(m^2)(p-1)}{p^k - 1},$$ where $\sigma(x)$ is the classical sum of divisors of the positive integer $x$, and $D(x)=2x-\sigma(x)$ is the deficiency of $x$.

We derive $$\frac{\sigma(m^2)}{p^k}=\sigma(m^2) - D(m^2)(p-1) = \sigma(m^2) - 2(p-1)m^2 + (p-1)\sigma(m^2)$$ $$=2(1-p)m^2 + p\sigma(m^2)=\Bigg(I(m^2)-\frac{2(p-1)}{p}\Bigg)\cdot{pm^2},$$ where $I(x)=\sigma(x)/x$ is the abundancy index of $x$.

Here is my question:

Is it then possible to get a positive lower bound on the quantity $$I(m^2)-\frac{2(p-1)}{p}?$$

Note that I know the following facts:

(1) $\sigma(m^2)/p^k \geq 315$ by a result of Broughan, Delbourgo, and Zhou.

(2) $2(p-1)/p < I(m^2) \leq 2p/(p+1)$ follows from $(p+1)/p \leq I(p^k) < p/(p-1)$

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On OP's request, I am converting my comment into an answer.

FYI :

$I(m^2)-\dfrac{2(p-1)}{p}$ can be written as

$$I(m^2)-\frac{2(p-1)}{p}=\frac{\sigma(m^2)}{m^2}-\frac{2(p-1)}{p}=\frac{2p^k}{\sigma(p^k)}-\frac{2(p-1)}{p}$$ $$=\frac{2p^k(p-1)}{p^{k+1}-1}-\frac{2(p-1)}{p}=\frac{2p^{k+1}(p-1)-2(p-1)(p^{k+1}-1)}{p(p^{k+1}-1)}=\frac{2(p-1)}{p(p^{k+1}-1)}$$

Let $f(k,p):=\dfrac{2(p-1)}{p(p^{k+1}-1)}$.

Then, we have $$\dfrac{\partial f(k,p)}{\partial k}\lt 0,\qquad \dfrac{\partial f(k,p)}{\partial p}\lt 0$$ and $$\lim_{k\to\infty}f(k,p)=\lim_{p\to \infty}f(k,p)=0$$