8 Global/7 JP and later has FeliCa secure element; checkm8 exploit works up to X. It’s a fine thinking to not accept secure transaction originating a potentially jailbroken device; perhaps that’s why?
(Interim while the above URL currently doesn't work: https://web.archive.org/web/20200217151824/http://ramtin-ami...)
The author(s) maintain the site out of personal interest.
It's very amusing that as you get to the bottom the "Vulnerable to" starts to disappear :) and yet you can download the bootrom anyway~ hmmmmm :D