The headword, illustrated by both of the quotations given, is present infinitive of the verb e)nde/xomai (for which cf. epsilon 1160, epsilon 1220).
[1] Procopius, History of the Wars of Justinian 6.20.14 (web address 1), with the words ou)k e)w=n – *belisari/ou added here as an explanation. For a brief history of this identification -- not in Adler -- see Theodoridis' Photius edition, vol.II p.XCIII. In December 538 CE, the Goth military commander Albila (cf. PLRE IIIa s.v. Albilas) continues to lead his men, surrounded within the city of Urbiventus (Velzna, Volsinii Veteres; present-day Orvieto, in central Italy; Barrington Atlas map 42 grid C3) and desperately short of provisions, against the siege by the Roman general Belisarius (beta 233); cf. Kaldellis (359).
[2] Quotation unidentifiable. (Adler suggests Aelian.)