just on this bit, saccato thetato i s a pretty rare phrase in the canon, it occurs at MN2, MN22, SN22.85, SN22.86, SN44.2, and AN3.61 and a further 11 times in the Abhidhamma.
All the SN occurrences are the same sutta repeated.
When they apply the mind irrationally in this way, one of the following six views arises in them and is taken as a genuine fact.
Tassa evaṁ ayoniso manasikaroto channaṁ diṭṭhīnaṁ aññatarā diṭṭhi uppajjati.
The view: ‘My self survives.’
‘Atthi me attā’ti vā assa saccato thetato diṭṭhi uppajjati;
The view: ‘My self does not survive.’
‘natthi me attā’ti vā assa saccato thetato diṭṭhi uppajjati;
The view: ‘I perceive the self with the self.’
‘attanāva attānaṁ sañjānāmī’ti vā assa saccato thetato diṭṭhi uppajjati;
The view: ‘I perceive what is not-self with the self.’
‘attanāva anattānaṁ sañjānāmī’ti vā assa saccato thetato diṭṭhi uppajjati;
The view: ‘I perceive the self with what is not-self.’
‘anattanāva attānaṁ sañjānāmī’ti vā assa saccato thetato diṭṭhi uppajjati;
MN2
“But since a self and what belongs to a self are not actually found, is not the following a totally foolish teaching:
“Attani ca, bhikkhave, attaniye ca saccato thetato anupalabbhamāne, yampi taṁ diṭṭhiṭṭhānaṁ:
‘The cosmos and the self are one and the same. After death I will be permanent, everlasting, eternal, imperishable, and will last forever and ever’?”
‘so loko so attā, so pecca bhavissāmi nicco dhuvo sassato avipariṇāmadhammo, sassatisamaṁ tatheva ṭhassāmī’ti—
nanāyaṁ, bhikkhave, kevalo paripūro bāladhammo”ti?
MN22
“In that case, Reverend Yamaka, since you don’t actually find the Realized One in the present life, is it appropriate to declare:
“Ettha ca te, āvuso yamaka, diṭṭheva dhamme saccato thetato tathāgate anupalabbhiyamāne, kallaṁ nu te taṁ veyyākaraṇaṁ:
‘As I understand the Buddha’s teaching, a mendicant who has ended the defilements is annihilated and destroyed when their body breaks up, and doesn’t exist after death.’?”
‘tathāhaṁ bhagavatā dhammaṁ desitaṁ ājānāmi, yathā khīṇāsavo bhikkhu kāyassa bhedā ucchijjati vinassati, na hoti paraṁ maraṇā’”ti?
SN22.85 SN22.86 SN44.2
Those who believe that past deeds are the most important thing have no enthusiasm or effort, no idea that there are things that should and should not be done.
Pubbekataṁ kho pana, bhikkhave, sārato paccāgacchataṁ na hoti chando vā vāyāmo vā idaṁ vā karaṇīyaṁ idaṁ vā akaraṇīyanti.
Since they don’t actually find that there are things that should and should not be done, they’re unmindful and careless, and can’t rightly be called ascetics.
Iti karaṇīyākaraṇīye kho pana saccato thetato anupalabbhiyamāne muṭṭhassatīnaṁ anārakkhānaṁ viharataṁ na hoti paccattaṁ sahadhammiko samaṇavādo.
AN3.61
So that’s the complete translation context for saccato thetato.
It is also the complete translation context for theta.
whittling down to thet gives one more context;
‘The ascetic Gotama has given up lying. He speaks the truth and sticks to the truth. He’s honest and trustworthy, and doesn’t trick the world with his words.’
‘Musāvādaṁ pahāya musāvādā paṭivirato samaṇo gotamo saccavādī saccasandho theto paccayiko avisaṁvādako lokassā’ti—
Such is an ordinary person’s praise of the Realized One.
iti vā hi, bhikkhave, puthujjano tathāgatassa vaṇṇaṁ vadamāno vadeyya.
DN1 and thereafter.
Theta (adj.) [Sk. from tiṭṭhita, Müller P. Gr. 7=sthātṛ] firm, reliable, trustworthy, true D i.4 (DA i.73: theto ti thiro; ṭhita – katho ti attho); M i.179; S iv.384 A ii.209=Pug 57; Nd2 623. – abl. thetato in truth S iii.112. – attheta J iv.57 (=athira).
Sacca (adj.) [cp. Sk. satya] real, true D i.182; M ii.169; iii.207; Dh 408; nt. saccaṃ truly, verily, certainly Miln 120; saccaṃ kira is it really true? D i.113; Vin i.45, 60 J i.107; saccato truly S iii.112. – (nt. as noun) saccaṃ the truth A ii.25, 115 (parama˚); Dh 393; also: a solemn asseveration Mhvs 25, 18. Sacce patiṭṭhāya keeping to fact, M i.376.
finally
Upalabhati [upa + labh] to receive, get, obtain to find, make out Miln 124 (kāraṇaṃ); usually in Pass. upalabbhati to be found or got, to be known; to exist M i.138 (an˚); S i.135; iv.384; Sn 858; Pv ii.111 (= paccanubhavīyati PvA 146); Kvu 1, 2; Miln 25; PvA 87.
words containing upalab occur very rarely in the 4 principle nikayas, and vastly more commonly in the late books.
People who defend the orthodox Theravadin sectarian commentarial interpretation of the ebt rely very, very heavily on a tiny number of suttas, a very disproportionate number of which contain these rare terms.
take it for what its worth.