USMMA produces restricted line officers, so they gave her a waiver because that issue doesn't preclude a commission in the SSO program. She could be active duty Navy in a restricted line, maybe like intel or something. But probably not in unrestricted line like aviation, SWO, etc.
No clear cut answer, but I do not think Restricted versus Unrestricted (excluding special duty fields) have different standards. I could be wrong though...
This is from the Manual of the Medical Department U.S Navy dated 3 Feb 2017. There are other items listed, but I believe visual acuity is what is being discussed. You see that for commission into the Navy Unrestricted and Restricted lines, they have the same requirement. It is
Entry into a Program leading to a Commission in the Navy Unrestricted Line that is different. The difference is the use of the words "OR" and "AND".
15-36 - Vision-Commission and Programs Leading to a Commission
"The standards for enlistment, commission, and entry into a program leading to a commission are different; refer to the appropriate section."
For commission in the Navy Unrestricted Line and/or commission of officers with intended designators of 611x, 612x, 616x, 621x, 622x, 626x, 648x, 711x, 712x, 717x, 721x, 722x, 727x, 748x:
(a) Current distant
or near visual acuity of any degree that does not correct with spectacle lenses to 20/20 in each eye is disqualifying.
...
For Entry into a Program Leading to a Commission in the Navy Unrestricted Line
(a) Current distant
and near visual acuity of any degree that does not correct with spectacle lenses to 20/20 in each eye is disqualifying.
...
For Commission in the Navy Restricted Line, Staff Corps, and designators not included above.
(a) Current distant
or near visual acuity of any degree that does not correct with spectacle lenses to 20/20 in each eye is disqualifying.
...
Using AND / OR logic...
Unrestricted & Restricted Lines
distant visual acuity = 20/20 (0 in this example)
OR near visual acuity = 20/20 (1 in this example) = 1 qualifying
For Entry into a Program Leading to a Commission
distant visual acuity = 20/20 (0 in this example)
AND near visual acuity = 20/20 (1 in this example) = 0 disqualifying