The tiny hole is not for timing belt inspection, but for aligning the engine at #1 top dead center. You won't see much in there, unless a camshaft oil seal or the water pump is leaking catastrophically and has sprayed oil or coolant all over the area (in which case you would want to get the belt replaced and deal with the source(s) of the leak, of course).
To inspect part of the belt you could remove one of the upper timing belt covers. They are held on by only five bolts. The front cover will probably be easier to remove/access. You have to move some wire bundles out of the way and possibly remove the oil dipstick as well, but you could remove it in less than 15 minutes.
The larger question is what would be served by inspecting the belt this way. You could see contamination on the belt, such as dirt, oil or coolant, but it is not clear that you might not see that the belt is close to failing. Many here report that their belts look 'like new' at >100,000 miles, though mine did look visibly older and was more flexible than the replacement I put on at 125,000 miles. However, failure of the timing belt would likely result from something internal to the belt, in between the plies, or due to weak 'teeth' that might break off.
The replacement interval is 105,000 miles or 7 years, whichever is first. In this subsection of the forum (99-04 Odyssey) these vans are between 6-11 years old. If yours is an 03 or older, you could be due for a belt change even though you have only 74,000 miles. The idea is that the rubber reacts with the air over time and becomes brittle. Many people on this forum wait past 120,000 miles as I did, but the longer you wait, the longer you risk a failure of the belt. If you take it to a shop you are looking at between $500-$1200 depending on shop rates and how much additional work is done. Many replace the water pump, oil seals, tensioners, spark plugs, and accessory belts at the same time. Many on this forum have done the job themselves and can get away with less than $400 in parts, depending on how much will be replaced.
You're in Florida, a relatively warm, humid climate. You might be able to wait for several more years before getting this done.