Don’t get Topeak Super Tourist rack

All standard racks are mounted with two bolts at the axle and two bolts up top. Your Topeak is no exception.

The other rack you linked to is unusual and not at all what people normally use for round the world touring.

I guess you had some kind of failure (you don’t say what it was), but the cause is probably not the design of the Topeak rack.

Did the bolts come with loctite/threadlocker on them? If they didn’t you should add the blue stuff. Probably prevents this from happening.

If your bolts are getting loose, degrease both the bolts and bosses in your frame and use appropriate threadlocking paste. Check a few times, apply some more if needed. If the bolt gets locked too firmly, these pastes usually soften with a little bit of heat. I can get a small tube, like 6 cm long for someting like 2 € and always carry it with other tools on my bike.

M5 x 0.8 mm (5 mm diameter, 0.8 mm thread pitch).
Length is usually 12–20 mm.

Weight capacity per bolt:
Typically around 10–20 kg per bolt, assuming they’re properly torqued into a solid steel or aluminum frame. Total rack capacity is usually 25–30 kg, not just limited by the bolts but also by rack and frame strength