I'll let brennus interest you with a lengthy historical reply as he is our "celt" expert and primary historian for Iberia. I can give you the short reasons for our decisions on those two units.

The dosidasomethings were indeed sketchy at best. They represented an elite and tribe specific (Vasci if I remember well) bodyguard unit. Obviously as the Vasci weren't a faction and it's evidence being limited, it didn't really had its place in EB I. The "Irish" or goidelic counterpart of this unit seems to had even less of an historical basis it appeared. Or at least we couldn't find and determine it historical basis.

There are indeed theories on a "Iberian"-"Irish" connection. As far as I seem to remember those are rather outdated. And surely the two units in question shouldn't be considered as an element of proof for this theory. Now let's wait for Brennus' answer. Hopefully I didn't post anything outrageous. Well except for using the word celt, which he apparently dislikes.