Hi everyone, in a bit of a tricky situation here. Here's the crank in question: https://tinyurl.com/3c4jpuu2

My Zrace RX crank uses a self-extracting cap + threaded 8mm hex insert on the drive side (like a dub). The torque spec outlined on the cap is 50 Nm and after taking the crank off a few times, the aluminum has totally stripped out of the 8mm hex key slot. The 8mm hex key insert is totally rounded out and I need to replace it, but the self-extracting cap requires a tool that looks like a large 8-sided flower (ie. shimano hollowtech, except it's way bigger, I measured the "flower indents" as 19mm across!).

The cap reads "16mm, 30Nm", but searching "16mm hollowtech crank cap extractor" yields no results, all the tools I can find are for standard smaller hollowtech cranks. I have no idea where I can obtain such a socket. Any clue?

Also, I was going to be replacing the crank cap assembly with a generic M18/M30 dub cap, has anyone done this successfully? Are there different sizes I should be checking before ordering? Here's an example of what I was thinking of getting https://www.aliexpress.com/item/1005003230950172.html?spm=a2g0o.store_pc_groupList.8148356.59.683b3a56UPLIDa

Edit: After 24h of searching, I  have found the tool in the bowels of Aliexpress, posting a link below for posterity. Still trying to figure out if the M18/M30 dub cap will work!
https://www.aliexpress.com/item/1005003801499299.html?spm=a2g0o.order_list.0.0.21ef1802aiovCn