My point wasn't that E-V13 is more important in Germany or Sardinia than in 'Albania, but that, going by the data, they play in the same league and e.g. Germany would likely exceed Albanian diversity if having the same level of testing.
My argument was, that both (Germany, Albania, Sardinia) are the result of later expansions and not part of the core zone. The core zone stretches from Transcarpathia to Central Serbia, from Nyirseg to Moldova in the LBA-EIA transition. From there they moved further down into the Balkans and in all other directions, even down to Greece and Troy - at least for a moment, with Channelled Ware.
But some of the core branches seem to have sticked together up to at least the later Iron Age. Just look at the TMRCA's in those main branches of E-Z5018 and E-Z5017. Some might have branched off and ended up in the Southern Balkans earlier, but the bulk looks like he wasn't much further South than the Danubian zone as the Southernmost point.
Since some of the Albanian branches have a TMRCA's in the Middle to Later Iron Age with Northern parallel branches of mentioned E-Z5018 and E-Z5017 in particular, and there is absolutely no indication that these branches were so far in the South before, and yes they even spread over the stepp to the Caucasus and Armenia, actually up to China, and at the same time to the West, to Central Europe, we have to assume they ended up in the vicinity of Albania fairly late. Most likely with resettled Daco-Romans and Dacian tribals.
Obviously we will see where we find the branches first, but as of yet, the E-V13 found in the Balkans were not the core branches (E-Z5018 and E-Z5017) which experienced the greatest continuous growth and seem to have formed the bulk of the E-V13 core population.
We will see where we find them, not just individuals, but many individuals side by side, with some diversity. But my best guess is not far from the Danube, definitely not South of Basarabi, most likely in the Dacians.
I predict, not with high confidence, but that's my best prediction right now, that we will find E-V13 in the Balkans South fo the Danube, South of Basarabi and the Dacians, but not a lot of the core branches, but older, more distinct ones. Like the ones we also find more often in the Near East and what we have found in in the ancient DNA record of the Southern and Eastern (Thracian) Balkans.
Those samples from Iron Age Bulgaria which could be assigned downstream both ended up in more remote branches. The single view which concentrates on non-E-Z5018/Z5017 branches of E-V13 covers most of the Balkan samples retrieved so far:
If one looks at E-Z5017/Z5018 in Discovery, the graph being dotted with Central European, mainly Hungarian, but not just, samples. The one from Viminacium looks like he's being Scytho-Sarmatian associated, going by the extreme distribution and presence in the Caucasus.
So even with the few ancient DNA samples, there is a clear trend towards the main branches being relatively more Northern (along the Danube and further North) rather than in the Southern or Eastern Balkans.
If you just think about the ratio, the number of samples, its astonishing that the Balkan samples dominate these branches, while even though we got many times more samples from other regions, they are not that common. Just three Hungarian samples! E-Z5018 has 19 samples from Hungary alone! E-Z5017: 9 samples from Hungary, again, not that bad and 3 times as much as for the ones common in the Iron Age Balkans.
These ratios just don't add up. What adds to this is that the only Iron Age sample from further South which falls into one of these branches, namely E-Z5017, is one of the Himerans!
And these were autosomally different too and might have been from a more Northern and/or Basarabi related context.
Indeed, there is a lack of Balkan samples so far, but why this odd ratio, especially in comparison to the Central European samples? Just compare:
https://discover.familytreedna.com/y-dna/E-V13/tree
Therefore we can say with fairly high probability that
the bulk (not necessarily all) of E-Z5018 and E-Z5017 likely lived either close to or North of the Danube even in the Iron Age. Most likely candidates are Basarabi and possibly other North Thracian/Dacian formations (Late Northern Gáva, Mezocsat-Vekerzug, Kustanovice etc.).