The only claimant argument we hear from Tigrays is that the region was part of tigray before Haileselasie's and Menilik's era, but they have never mentioned the status and demography of the region as to what it looked like before Haileselasie and Minelik. There is also no evidence of Menelik and Haile Selassie carrying about Raya
The Emperors even incorporated many areas that are not wollo into wollo like Mekdela, Sayint Amhara, Lasta, Sekota
Because Meles Zenawi put the region under the administration of Tigray, and because that was accepted at the time by Amhara since Tigray are their citizens with whom they share history, religion and culture, that doesn't make the region Tigray land for good.
However, Amhara now starts showing a tendency of secession just like their cousins Eritrean Kebessas. The Eritrean Kebbesas snatched Assab and Dankalia territory and left us with a huge task to bring that back.
Worbela Shifta Agame Tembien Lebas would be lucky on this one.