Looks like 75grams of dextrose and 75 grams of sucrose, 150grams of sweetener in 10oz is a metric fuckload of sweetener. It’s basically syrup at that point.
I got curious and grabbed my bottle of maple syrup out of the fridge. It’s got 24g of sugar per 2tbsp serving (24g/oz), so it would need to be diluted to 60% strength to match this oral glucose test drink.
On a related note, I just drank 1.5oz of maple syrup diluted to 2.5oz of total volume, as a little experiment. Not too bad; I could do that three more times if necessary for a medical test pretty easily without complaining. Definitely sugary enough that drinking it makes you thirstier instead of refreshing you, though.