Merriam-Webster records that many Americans pronounce - and some spell - "bologna" (sausage) as "baloney" ( https://www.merriam-webster.com/dictionary/baloney ):
baloney noun (1) \ bə-ˈlō-nē\ less common spelling of bologna : a large smoked sausage of beef, veal, and pork also : a sausage made (as of turkey) to resemble bologna
However, it doesn't work the other way round. "Baloney" (meaning "nonsense") doesn't have a variant spelling "bologna".
Still, the fact that some people pronounce them the same way (and some people use the spelling "baloney" for both) means that misspelling "baloney" (nonsense) as "bologna" would be an understandable mistake. (In this case, the mistake may well be on the part of a non-native speaker, since the phrase "utter bologna" was apparently found in a South American source.)
Alternatively, it could be a joke, as others have said. (Either way, googling "utter bologna" brings up a fair number of hits.)
The notion that "baloney" (nonsense) derives from "bologna" is conjecture, according to the OED, but seems atractive.
Whether or not "baloney" originated as a euphemism for "bullshit", some people clearly regard it as such. But the two words are not similar enough for "baloney" to cause any offence (at least, no more so than calling something rubbish or nonsense would).