That parachute looks comparatively tiny, but the typical wing loading for a newbie will have you descending at 15-25mph (20-40 feet per second, approximately). I think I remember an advanced canopy instructor mentioning that with his high wing loading, he could hit 100mph or so (150 feet per second, give or take) in a diving turn. Interestingly, if there is no landing with the bottomless pit, you could give newbies advanced canopies without too much worry. Sure, there's a chance they fuck up the lines and ruin the experience, but they could just cut away and then enjoy the freefall.

Let's just say this fella was given an appropriate newbie-sized canopy for his weight, and is at the lower end of the spectrum. A typical fall rate for a belly-to-earth orientation (which is the beginning orientation taught, as it's the most stable and easiest to manage) will be between 100-125mph (150-180ish feet per second). That's a difference of ~1:4, which means if your fastest decomposition occurred, our freefaller would be a week in his fall already, and probably dead himself... IF the canopy dude had died immediately upon entering. That would make sense, seeing as how it's a bottomless hole, not an entire world. He's probably bounced off the sides a few times. Hitting a cliff face is the beginning of death for most base jumpers, so it could be our friendly pilot's cause of death here.

BUT let's not jump to conclusions too quickly. If this dude is decomposed, that means quite a bit of weight is gone. My search history has probably just gotten mildly spicy for an investigator somewhere. A quick search showed a graph of decomposition reducing weight by approximately 70-90%. That means our pilot here might have gone from a conservative wing loading of 0.8 to something like 0.2. That's going to be suuuper floaty. The vast majority of the weight comes off after bloating stops and the active and advanced decomposition sets in. So let's say by day 15 (to make the math easier), the canopy pilot is only falling at a rate of 8 feet per second. I don't want to actually break out the calculus, so simple arithmetic and algebra here. We'll take the difference between 8 and 20 feet per second and multiply that by 15 days worth of seconds, then see how long it takes our freefaller. So by day 15, canopy-man is at 18,144,000 feet in the pit. He's now descending at 8fps, compared to the fastest 180fps of the freefaller. The freefaller gets to 18,144,000 feet in 28 hours. The canopy is another 806,400 feet down. In another ~1.3 hours, the freefaller catches up. I think our comic is a possibility now.

We could also say that our freefaller is quite experienced, or very inexperienced, and is vertical more often, which typically sees speeds closer to 180mph, or around 250-300fps. That changes things again (and really makes the scenario easy), but meh. Do the math yourself, nerds.