Kakacūpama Sutta and Mistress Vedehika

My take on that sutta is that , you can't really tell if one is kind or gentle in a normal situation but rather when he (or she , Vedehika in this case) is under stress. Sort of like you can kinda tell if one is coward or brave when he is in a dangerous situation.

The explanation of whole kakacūpamasutta:

After Buddha blamed Moliyaphagguna in Sutta. Ma. Mū. kakacūpamasuttaṃ, he rejected the monk hood to be a lay in Sutta. Saṃ. Ni. kaḷārakhattiyasuttaṃ. In that, kaḷārakhattiyasuttaṃ, Kaḷārakhattiya bhikkhu talked with Ven.Sāriputta "the mendicant Moḷiyaphagguna has rejected the training and returned to a lesser life." So, Buddha began the second part of kakacūpamasuttaṃ to explain & to teach the left bhikkhu by Moliyaphagguna-rejection case.

Moliyaphagguna can not patient to co-temple bhikkhus' and Buddha's blame, because he was unruly, unteachable by his annoy--dosa. He annoyed after he was blamed, so then he rejected the monk hood. Therefore Kaḷārakhattiya bhikkhu talked with Ven.Sāriputta "the mendicant Moḷiyaphagguna has rejected the training and returned to a lesser life."

Buddha began the second part of kakacūpamasuttaṃ to explain & to teach the left bhikkhu that whoever can pause annoy--dosa-mind, by mettā-meditation, they can patient to listen and to train follow Buddha's teaching such as "only 1 period meal vinaya-rule". Then they will "come to growth and development in this dispensation of the Teaching" like buddha said in kakacūpamasuttaṃ.

But the training is not too easy like that, some time there are hidden enemies such as hidden annoy, etc. So, Buddha said "Like a Sal grove near a village or hamlet would have an undergrowth of weeds" and put the Vedehikā example in kakacūpamasuttaṃ to let bhikkhu more careful about the hidden annoy before they will be blamed by the others.

Then Buddha taught "others speaking would speak in this fivefold way" and many similitudes to bhikkhu, because Buddha let them prepare themselves before the annoy will arise at listening blame. By this teaching, bhikkhu will have enough mettā to patient for the blame listening, then they can practice follow to the blame "to come to growth and development in this dispensation of the Teaching".

I'm not sure sure if this is opinion based or not but my question is. is it fair to judge Vedehika, poorly (and does the sutta really do this). It seems like she was pushed to the breaking point

Well, simply by going with what's described in sutta MN 21, it doesn't seem like Vedehika was really that gentle and peaceful. Let's see her reaction the very first time her maid Kali got up late:

“So the maid Kalı got up late. Then Mistress Vedehika said: ‘Hey, Kalı!’—‘What is it, madam?’—‘What is the matter that you get up so late?’—‘Nothing is the matter, madam.’—‘Nothing is the matter, you wicked girl, yet you get up so late!’ and she was angry and displeased, and she scowled."

And then what she did the last time being tested:

‘What is the matter that you get up still later in the day?’—‘Nothing is the matter, madam.’—‘Nothing is the matter, you wicked girl, yet you get up still later in the day!’ and she was angry and displeased, and she took a rolling-pin, gave her a blow on the head, and cut her head. Then the maid Kalı, with blood running from her cut head..."

Now whether it was a true story doesn't matter much for it was a simple analogy the Buddha used to really drive home the point of a very real issue for many monks:

So too, bhikkhus, some bhikkhu is extremely gentle, extremely meek, extremely peaceful, so long as disagreeable courses of speech do not touch him. But it is when disagreeable courses of speech touch him that it can be understood whether that bhikkhu is really kind, gentle, and peaceful."