You say you know the case - but you must have left out some aspects … you say …
What facts were presented in support that she did not know what she was getting into? …
Did you know the couple before they married?
Did they live together or engage in sexual relations before marriage?
Was there abuse in either household growing up whether sexual, substance, physical?
How long did the couple know each other?
Did they use ABC in the marriage?
Are both active practicing Catholics?
I personally know many priests - not one of which would accept a case if someone walked in and said - I did not know what I was getting into when I married and I have a new boyfriend I want sleep with while actively practicing my faith …

They would require far more information then that. So they must have given more then what you presented.
What matters is the conditions that existed at the time of the marriage - behavior [like using ABC] can be an indication of the conditions that existed - not being open to life … or finding out that one of the parties had sex with a third person a month before the wedding as well as other adulterous relationships after could indicate they had no intention of fidelity …
A marriage contracted because of a pregnancy is not being made freely without pressure - laudable as it may be …
A young woman who is from a home where abuse is present may see it as an escape route - only to escape into a different kind of hell - even if they did not fully realize that is what they were doing at the time due to immaturity or other stress …
It is not as easy as you might think to obtain an annulment … and one of the complaints on your favorite website is the depth and personal nature of the questions being asked … they complain that there is something wrong - but also complain about the investigation being too intrusive … You cant really have it both ways …
I also note there is no real angst about the civil aspects - is it really so much worse to determine that the couple did not fully comprehend the vow they were making when they made it - more so then that the marriage ended by divorce … For example - the daughter’s story - she is not greatly concerned that her parents are divorced - actually seems somewhat relieved - but very concerned that the Church states no Sacramental marriage occurred. She indicates that her father is unstable - not wanting children … Would that not give credence that he was not well prepared for marriage? The real tragedy here is that her parents [both of them] failed to provide a stable home for her and her sister - instead of voicing that - she is mad at the Church.
I think people mourn the death of their marriages, it is not easy to fail at one of the most important life events you experience - one that is very public and involves a wide circle of people [children, family and friends] -
The annulment process can help them understand why it failed - even if the validity is upheld - thus it should be a positive process that can prepare them for future relationships … whether that is a renewal of opportunity for those whose marriages are upheld to rethink their separation/divorce, for those who might later marry again due to the decision - or those who know with certainty that they cannot date and marry because their marriage was determined valid …