ἰσότιμος, ον (s. ἴσος, τιμή; Strabo 15, 3, 20; Dio Chrys. 24 [41], 2; Plut. et al.; OGI 234, 25 [c. 200 B.C.]; 544, 33 [adv.]; PRyl 253; Mitt-Wilck. I/2, 13, 10; Philo; Jos., Ant. 12, 119; Ath. 22, 2) gener. ‘equal in honor/value’, also simply equal, like, of the same kind/value (Aelian, NA 10, 1; Herodian 2, 3, 6; Herm. Wr. 12, 12; Jos., Ant. 12, 3, 1 ‘equally privileged’) ἰσότιμον ἡμῖν πίστιν a faith of the same kind as ours = faith w. the same privilege as ours (i.e. the recipients are not less advantaged than the apostles) 2 Pt 1:1. Cp. SJCh 92, 1–3.—M-M. TW. Spicq.
Arndt, W., Danker, F. W., Bauer, W., & Gingrich, F. W. (2000). A Greek-English lexicon of the New Testament and other early Christian literature (3rd ed., p. 481). Chicago: University of Chicago Press.
As for λαγχάνω, what makes best sense in context?
λαγχάνω 2 aor. ἔλαχον, subj. λάχω, ptc. λαχών; pf. 3 sg. εἴληχεν (Ath., R. 13 p. 63, 27; LMelazzo, Glotta 71, ’93, 30–33), ptc. λελογχώς 3 Macc 6:1 (Hom.+) for its constr. s. B-D-F §171, 2; Rob. 509. Pass. of κληρόω.
① to obtain someth. as a portion, receive, obtain (by lot, or by divine will; Hom.+; IPriene 205, 2; PTebt II, 382, 5; 383, 14) τὶ someth. ἔλαχεν τὸν κλῆρον τῆς διακονίας ταύτης Ac 1:17. πίστιν 2 Pt 1:1.
② to be selected through casting of lots, be appointed/ chosen by lot (Hom. et al.; Pla., Pol. 290e ὁ λαχὼν βασιλεύς; SIG 486, 9; 762, 12 λαχὼν ἱερεύς. Oft. used sim. in ins; Jos., Bell. 3, 390. In the broader sense ‘befall’: ApcMos 15 τὸ λαχὸν αὐτοῦ μέρος ἀπὸ τοῦ θεοῦ.) ἔλαχεν τοῦ θυμιᾶσαι he was chosen by lot to burn incense Lk 1:9 (on the constr. s. B-D-F §400, 3; Rob. 1060; 1 Km 14:47 v.l. Σαοὺλ ἔλαχεν τοῦ βασιλεύειν).
③ to allot a portion or make an assignment by casting lots, cast lots (Isocr. 7, 23; Diod S 4, 63, 3b) περί τινος for someth. (Ps.-Demosth. 21 Hyp. 2 §3.—B-D-F §229, 2; s. Rob. 509) J 19:24. λάχετέ μοι ὧδε, τίς νήσει τὸν χρυσόν cast lots, now, for the one who will weave the gold (for the temple curtain) GJs 10:2, w. some mss. adding καὶ ἔλαχεν τὴν Μαρίαν ἡ ἀληθινὴ πορφύρα and to Mary fell the lot of (weaving) real purple (i.e. high-quality fabric colored with the dye of shellfish rather than cheap imitations made w. vegetable or other dyes).—DELG. M-M. TW. Spicq. Sv.
Arndt, W., Danker, F. W., Bauer, W., & Gingrich, F. W. (2000). A Greek-English lexicon of the New Testament and other early Christian literature (3rd ed., p. 581). Chicago: University of Chicago Press.