Thats excactly what I thought too, dlsym is patched by goldhen (and by mira if you use that insted) so it is not needed in the kernel exploit.
I also had some strange behaviour testing the pull request version. It seemed to work ok just using his files but when I tried to implement it into the prb menu the kernel exploit it kept saying jailbreak failed.
I looked into the problem and it seemd that the kernel exploit was returing main_ret 91 instead of main_ret 0.
Everthing still appeard to work correctly but no idea why that was happening.
In the end I've just used sleirsgoevy's offical release in the prb 672 update and all is good.