The Sūdovians adopted a Wielbark Gothic like weaponless burial observance. The Tiberius coin from Pajevonys, LT would suggest the interaction lasted for centuries. Inter-marriage probably was not uncommon. Ancient Wielbark culture  Mtdna H5a1 would seems to support such mixing with Balts. The higher than expected frequency of the LWb+ antigen - LW*07 allelle ( aka Nea red cell antigen ) in Hungary ( 0.4% ) may well be related to the Goths, since southern Sweden had a similar ( 0.3% ) frequency, and Gotland has even more ( 1.0% ).

Lithuanian linguist Kazimieras Būga derived Lith. vokietis from the old name of the Gotland Vagoths ( re: Icelandic vogur, Shetland voe, Finnic vuojola, Sami vuowjos ). It is not a stretch to imagine *vāg-aitis > *vog-aitis > vokietis "Gotlander > seafarer", or "foreigner" . Contacts were quite common ( re: LWb+ in Gotland ). The Nydam axe "vagagastiz" may suggest Lith. vokietis reflects an older "wave-traveler", "seafarer" or "foreigner" term using related Scandinavian ( Old Norse Vágr - sea, wave ) terminology. Such a bi-lingual etymology of "vokietis" may well reflect prolonged bi-lingual contacts as expected near Grobina / "Seeburg", or perhaps Kaup, between Gotlanders & Balts ( Gotlandic would adopt Baltic loanwords for Gutnish "kleti" - barn, and even Gutnish "mausä" - fly, insect ), and "vokietis" would persist with the evolving semantics of "Germanic seafarer" > "Germanic speaker".

The 3rd-5th century "conversion" of "East Germanic" Gothic & Vandalic to "North Germanic" left scattered traces of it's earlier use, just as West Baltic dialects left relics spoken after East Baltic dialects quickly replaced them. A comparison of Gothic "saiso" with Old Norse "seri" provides evidence for reduplication hidden by rhotacism. Finnish and Estonian still use "ja" reflecting a Gothic "jah". Continental  Gothic was  essentially a socially disconnected outlier from the W. to E. sweeping changes ( with umlauts & rhotacism ) that took place back in Scandinavia, which fortunately survived intact as Wulfila's  written Gothic of the Codex Argenteus. Trade contacts ( preceeding Hedeby / Birka ) would also export &  accelerate the newer infectious speech changes adopted in other distant regions with trading centers. With trade came a social attraction to innovation. The runic scholar, Henrik Williams, has noted that there is a boundary in dialect discernible in runic inscriptions between the south-west and north-east (Williams, 1996: 439). That boundary survives as a relic, reflecting the forgotten past, & now forgotten languages.

Recomended Reading / References

"Den gotiske sprogklasses indflydelse på den finske",
A dissertation by the Danish scholar Vilhelm Thomsen (1869)

"PRELITERARY SCANDINAVIAN SOUND CHANGE VIEWED FROM THE EAST",
by Johan Schalin, Nordica Helsingiensia 54 ( Journal )

During the Wielbark culture, and the later cultural fusion of the Wielbark-Chernakhov Culture era, a West Baltic "kanãpis" agricultural term was probably borrowed as *"hanapis" into some 1st-2nd century Gothic dialects of southern Scandinavia. The earliest evidence for hemp cultivation in Scandinavia, specifically in the Malmo region of southern Sweden, began during the 1st-2nd centuries AD - centuries after Wielbark contacts & cultural mingling with various West Baltic speaking tribes.

The dialect characteristics of Wulfila's Biblical Gothic, like the Samlandian of the Prussian Catechisms, invites a heuristic approach. Weilbark settlements were often a mile or two from the villages of West Baltic speaking trade contacts. Hails / Kails.

So Goths came from Götaland, like Sūdovians came from Sūduva. Who knew?

Ptolemy.

Nobody "Vanished".

Ptolemy's mention of the Γαλίνδαι & Σουδινοί in the 2nd century
is reflected in Yfull samples, Mazovian id: YF03538 w/ R-YP4638,
& Sudovian id: YF86015 w/ R-BY164240.

ᛗᛖᛊ ᛈᚨᛚᛁᚲᛊᛁᛗ

Götaland <  R-YP4638  > Galinda (Mazovia)
Götaland <  R-BY164240  > Sūduva (Suvalkia)

"What happens in Vegas, stays in Vegas"