Not sure what's on the website right now but I've never had any trouble using my ticketed baggage allowance (Flex = +10kg, Top = +20kg) & then having my LatramPass Black 20kg added on top.
The only issue that I have seen is that the emailed ticket which most people print out only shows a 23kg baggage allowance(regardless of whether you book Basic, Flex or Top), so I have had checkin agents add 23kg + my LatamPass Black 20kg & advise my limit is therefore 43kg, however they've always quickly adjusted that limit to 63kg when I point out that I booked a 'Top' fare, which shows on their system but not on the printout.