PMC Sierra SPC SAS-SATA Card + ESXi

So I got this weird setup, where I need to passthrough a PMC-Sierra PM8003
card (same as PM8001, but with external QSFP afaik) to FreeBSD 11-STABLE
running in ESXi.
The card works fine in baremetal FreeBSD 11. Boot is ok, all disks
detected. When done in ESXi with passthrough though:
1. First try, host crashed with PSOD. After tweaking passthrough.map in
esxi to do d3d0 reset, host does not psod anymore.
2. FreeBSD kernel panics at pciAttach. After analyzing the driver
(sys\dev\pms), turns out it only works in MSI-X mode. Disabling
msi_blacklist in loader.conf makes FreeBSD not panic.
3. FreeBSD deadlocks on boot. After analyzing the driver more (turning on
all debug features, and adding a few extra), I got this log (pastebin link:
https://pastebin.com/cEGwFZZ2). The code tries to initialize SGPIO, but for
whatever reason does not get an interrupt reply when run on ESXi which
makes it loop for infinity waiting for said interrupt.

The deadlock happens in the

    while(!sgpioResponseSet)
    {
tiCOMDelayedInterruptHandler(tiRoot, 0, 1, tiNonInterruptContext);
    }

section of SendSgpioRequest in
sys\dev\pms\RefTisa\tisa\sassata\common\tdport.c

Sgpi seems not-so-critical feature to me, so I just limited the while loop
to 100 iterations, which lets SendSgpioRequest return an error that is not
considered fatal, and lets the code execute further which can be seen in
the log: https://pastebin.com/Rk6MD5ci (disregard the final fatal trap, I
think it is caused by me and/or my debugging code, same modifications
without debugging features do not trap and I get same trap on baremetal
with my debug kernel).

With those modifications, pciAttach is successful, I finally get a boot,
the card exists in lspci, BUT no drives connected to it are detected.

At this stage, I am out of ideas, looking for suggestions.