Grammar lessons!
The functional difference between the two words is that "real" is an adjective, where "really" is an adverb. You seem pretty fluent, so forgive me if this comes off as condescending or is too elementary.
"Real good" is wrong because "real" an adjective attempting to augment another adjective. It's similar to saying "The Wild's alternate jerseys are big green" (as opposed to the correct descriptor of "dark green").
"Really" has the same base meaning as "real" (as they're from the same root
), but is the adverb form which makes it appropriate for modifying the descriptor on Granlund's well being.
This particular example, as TGF explained above, is pretty common in certain regions in the US (particularly the south). Unfortunately, though, it's far from grammatically correct. The speaker means to use "really," but they're close enough that most people can figure out their intent and no one bothers to correct it.