Paul Nassif -- Carnival Workers Vouched for Me ... My Son Fell Off a Ride

Paul Nassif wasn't lying when he claimed his 6-year-old son sustained hand injuries by falling off a carnival ride ... this according to carnival workers who filed an injury report that completely backs Paul's story.

The question ... was Adrienne Maloof lying when she told Children Services Paul abused the kid?

TMZ obtained the report, filed by two carnival workers moments after Christian injured himself on November 11.

According to the report, the carnival workers ... Christian "jumped off steps of ride exiting, fell on his hands." And that's how he was injured.

The report adds, "[Christian] wiped his hands off and didn't seem very concerned."

According to the report, the injuries to Christian's hands were nothing but a "slight scrape."

The account flies in the face of the story Adrienne told to the L.A. Dept. of Children and Family Services -- that the child was injured when Paul kicked him.

Adrienne was concerned Christian suffered broken fingers -- but the report says he was so unfazed, "he continued to ride other rides."

DCFS is currently investigating.