That could describe the situation when you're drinking MSG-laced soup. The liquid will race ahead of the solids ingredients like noodles and get absorbed first.
If MSG is sprinked onto something dry, like some types of snack food, which is then washed down with a drink, it could also be absorbed fast.
This is first-principles message board hypothesizing. In fact, there's enormous incentive in academic science to actually demonstrate a reliable adverse MSG effect, and there has been for decades. Why has no reputable study done so? Is it really your argument that no food scientist has ever thought of the study design questions you're alluding to here?
If MSG is sprinked onto something dry, like some types of snack food, which is then washed down with a drink, it could also be absorbed fast.