Learn English – Is “raises question marks over” a correct and common phrase

I'm sure the reporter knew perfectly well the implications of using to coin a phrase, and it wasn't an "ironic" usage in the sense that people say this when trotting out a cliche. It's a tichy (tongue-in-cheek) example of typical British understatement.

Barry Kilby (manager of Burnley Football Club) has said more than once that he wouldn't bet the ranch on the outcome of an upcoming game. The reporter is slightly niggled by this, since the standard (particularly in the UK) expression is bet the farm. She's even more niggled because we don't even have "ranches" in the UK - but we do have a preponderance of foreign (including American) managers of our football clubs.

Personally I think the reporter is taking two or three good-natured pops at what she sees as legitimate targets, while showing her own skill at writing by doing this in so few words.

Edit: Having not actually followed OP's link to the newspaper report itself until now, I've just somewhat sheepishly changed the gender of my pronoun references to reporter Suzanne Geldard.

The only real justification for seeing dialog as "American" is that there are many words where US spelling seems more "logical" than British - largely thanks to Webster, though so far as I know he never addressed this particular issue.

Paraphrasing grammarist.com's entry on another such word: all early editions of Noah Webster’s dictionary list catalogue, but by the 1890s catalog was commonplace in AmE texts (Webster often gets credit for changes he played no direct part in).

There aren't many written instances of dialog prior its rapid uptake by software-oriented writers, but here's one from 1910 Transactions and proceedings of the American Philological Association, where one might reasonably suppose the author to be perfectly literate.

I think it's just that on average people involved in technical writing are more inclined to ignore precedent and go for what seems to them the logical spelling. Consequently we see the short form much more often in computer contexts such as dialog box, leading many people to suppose there are in fact two different words involved (or at least, that the word has two different spellings dependent on context).

It seems to me usage is currently in a "transition phase", but most likely the shorter form will continue to encroach further into traditional, non-computer contexts, and will eventually be seen as standard for all contexts (but for most people, particularly Brits, this hasn't happened yet).