I'm going to respond to various components of your post, individually.

1)
Originally Posted by HighIQ
Is there something wrong with my old school district's gifted and talented program's means of identifying gifted and talented students... They use the CogAT and the Torrance tests of creative... teacher recommendation...
These are fairly common test instruments, however it is unknown what criteria was used, and with what frequency students were identified and added to any gifted programming. A teacher recommendation can be used in different ways, for example, to cast a wider net and gather in pupils who may not have received qualifying scores... or to identify and screen out pupils who would not be a good "fit" for the school's gifted program.

2)
Originally Posted by HighIQ
valedictorian... admission into Yale
- A valedictorian is typically the Senior who had the highest grades at the end of Junior year. If there is a tie, this may be resolved in a different manner at various schools. Valedictorians are sometimes known to "coast" once they have received their title/label.
- According to recent US News College Rankings, Princeton is #1, Harvard #2, Columbia #3, MIT & Yale tied at #4.
- While PolarisList does not specifically track feeder schools for Yale, it may be of interest to see whether your alma mater high school is a feeder for Harvard, Princeton, MIT.
- Overall, there may be nothing unusual about a valedictorian receiving an offer to attend their State flagship and/or one or more top national colleges/universities.

3)
Originally Posted by HighIQ
cheating
...
I assume that she did this all the time throughout all her years at the high school.
This is a strong allegation or accusation to make. Casting aspersions on someone's academic integrity by hint, rumor, and innuendo of cheating and/or plagiarism could backfire with counter-measures such as accusing you of libel, slander, or defamation. There are various degrees of "help from other students to get higher grades on tests by asking them what will be the test questions and how to answer them and such," some of which may be considered ethical and a sign of healthy relationships and teamwork, some of which may be considered a gray area, some of which may result in expulsion and/or charges. For example: attending and/or discussing a test-sponsored prep session is a positive and shares detailed questions and answers from previous versions of an achievement test (which have specifically been released for study purposes); by contrast, stealing a teacher's test answer key is verboten. Meanwhile, measures exist to counter common gray-area exchange of answers (such as creating multiple versions of tests).

4)
Originally Posted by HighIQ
toxicity
Whether your concerns about events you may have witnessed are just surfacing belatedly now that you are no longer in the potentially intimidating school situation... or whether you may be emulating others by engaging in a bit of a smear campaign which seemed to work for them, enhancing their power, influence, and status... or whether you are stuck and unable to move on... it is best for your sake if you are aware of the impact of your words on others you encounter and/or interact with. This story sums it up well:
Originally Posted by Psychology Today
Early in my career, I was collaborating with a senior colleague to write a research grant. As we discussed previous research, I was particularly critical of other researchers. My colleague, who was also an early mentor in other aspects of my life, brought an abrupt end to my comments. In a supportive but rather blunt way, he simply said, “There are two types of people, those who contribute and those who detract. You must learn that the best way to build your career and your life is through your own achievements, not by attacking the achievements of others. People will always remember what type of person you are, and they will trust or distrust you accordingly.”

Seldom have I heard words that were truer or more genuinely wise. People who have only criticism to offer are soon forgotten—those who contribute in a constructive way become part of history.
5)
Originally Posted by HighIQ
I would estimate her IQ to be in the 110-125 range
To a casual observer, it would seem that one would not typically have access to data and information needed to reliably assess another's IQ. You've made several posts with conjecture on other's IQs. This may be an unhealthy obsession with others' lives. A few other members have previously suggested this, with differing degrees of sensitivity and bluntness. I have attempted to show that it is not realistic to beat your former classmates in every area of life as this sets up several goals with inherent conflicts to each other.

6)
Originally Posted by HighIQ
110-125 range, which is obviously not gifted
There is no one definitive answer as to giftedness. However, in some contexts, anything over the average 100 IQ may be considered gifted. Here are some examples of gifted IQ ranges:
- Ruf, 5 levels of gifted - https://www.nypl.org/blog/2015/04/02/booktalking-5-levels-gifted (120 +)
- Hoagies - IQ depends on the test instrument utilized - https://www.hoagiesgifted.org/highly_profoundly.htm (124 +)

7)
Originally Posted by HighIQ
I didn't get in the program...
possibly due to low scores...
I think it was because of the horrid teacher recommendation that I didn't get in
As you've previously posted about attitude, that may suggest it was not test scores, but rather questions/issues as to "fit" with the program.