YEAH! What they said.
Just because it was well written by an apparently intelligent person with a good vacabulary who can form proper sentences & paragraphs free from misspellings, and knows how to post pictures does not mean it's fake.
If a post said:
help my chickens r sik dey dont eat wat do u do dey r swet chickens i hatch dem from egs last year
There would be no doubt in our minds that it was legit.
Grammar isn't the reason why anyone has voiced skepticism though.