I used the Perseus site to peruse texts that refer to Vatinius but most of the ones that interested me were not readily available in Latin on that site. Cicero made a very long speech in the Senate called In Vatinium against Vatinius where he makes reference to Vatinius being denied augership. He also refers to the disfigurement in his letters to Atticus and in one to Brutus. What word did he use in In Vatinium? "Ista quae sunt inflata" or those disgusting things which are swollen. The English translation at Perseus rendered 'ista' which is a pronoun into the word 'wen'.
Catullus came to my aid, good ole Catullus. He wrote a poem, now called 52 but at the time was called In Novium, in which there is a line calling Nonius 'a giant boil sitting on the curule chair'(my translation) and accusing Vatinius of perjury. Who is Nonius and what exactly is a struma anyway? So I looked in my pocket dictionary The New College Latin and English Dictionary. It also includes Late Latin and Neo Latin so it has been useful for some Medieval texts. In this dictionary, struma means 'tumor, swollen gland'; however just after this entry is strumosus which means scrofulous.
Not content with this, I got out the granddaddy of Latin dictionaries, the Oxford Latin Dictionary, because it has only classical Latin and some etymology plus where words occur in Latin texts. I love a good dictionary. I should have gone to this one first as nearly all the entries where struma occurs also contain the name Vatinius. There is nothing like being famous for all time for a giant boil on your neck.
The OLD defines struma as 'a swelling of the lymphatic glands'. Strumosis is 'afflicted with glandular swellings'. This requires now a look at the Oxford English Dictionary and, indeed, scrofulous comes from a Medieval Latin word 'scrofula' which means an enlarged lymph gland. Maybe struma is scrofula but there is more reason that one for enlarged lymph nodes. Scrofula is derived from scrofa, which the OED states is latin for 'breeding sow which were deemed subject to this disease'. Struma was equated with goiter, bronchocele or scrofula at the earliest in 1400 in Lefranc's Cicurgie. So whatever dictionary, if he was conducting his research in the original latin texts, he used may have been like my pocket dictionary - spoiled with Medieval Latin terms - or whatever translation he used of those texts had been spoiled with Medieval Latin terms.
The OLD lists In Vatinium 39 "si...strumae ab ore improbo demigrarunt et aliis iam se locis conlocarunt"(if those tumors migrate from your shameless face and now lodge themselves in other places), Letters to Atticus 2.9.2 "licet....Vatini strumam sacerdoti vestiant" (it is permitted that priests adorn the glandular swellings of Vatinius) and Celsus V.29.2"struma est tumor, in quo subter concreta quaedam ex pure et sanguine quasi glandulae oriuntur...nascuntur maxime in cervice, sed etiam in alis et inguinibus" ( A struma is a tumor, in which arises under certain curdling from pus and blood just like of a small gland.... it is borne mostly in the neck but also in other private parts.) Most English translations of these texts call struma 'scrofula'. Pliny's Natural History is full of references to scrofula including how to cure it with weasel's blood. So Harris is not wrong to say that Vatinius had scrofula but I wonder if later translators had been duly diligent in naming the disease or just followed what previous translators had done.