What's so difficult to understand? For Matzinger, Albanian is a different language (not the same, not a linear descendant) from Illyrian AND closely related to it:
Matzinger (2018), Lexicon of Albanian, Handbook of Comparative and Historical Indo-European Linguistics
[....] Albanian cannot be regarded as an offspring of Illyrian or even Thracian but must be considered to be a modern continuation of some other undocumented Indo-European Balkan idiom. However, Albanian is closely related to Illyrian and also Messapic (a language spoken in Southern Italy in antiquity but originally of Balkan origin), which is why Albanian in some instances may shed some light on the explanation of Messapic as well as Illyrian words (see Matzinger 2005): (Messapic-) Oenotrian ῥινός ‘clouds’ ~ Old Geg rẽ, Old Tosk rē ‘cloud’, the Messapic gloss βρένδο- ‘stag’ and the place-name Brundisium (Italian Bríndisi) ~ Old Geg brĩ, or the name of the Illyrian tribe of the Taulantioi ~ Albanian dallëndyshe ‘swallow’ (see Eichner 2004: 10 f.).