Cisco SG300-28PP Self "Refurbished" boots but no Console.

Story time: (tl;dr at bottom)

Scored a great score. The work ewaste (read: if it gets "disposed" into an employees car, nobody cares :D) had this beauty.

I take it home. I plug it in. DOA. Makes sense (was hoping for maybe a dead port instead of a totally dead switch, but ... cont'd!)

Take the shell off. Was gonna check the fuse, but ... where's my multimeter... Shit. Oh well lets just plug it in to see... Hmmm a light. Maybe an LED? but why? .. couldn't see it outside of the case.

So I unscrew the daughterboard (which looks like it's for the POE side of things) which the flash of light on plug in. was originating from. Flip it over and try power on again. ZZZT SPARK! Then I notice it, clearly, a damaged ceramic surface mount cap (very small). There's a bit of a skid mark of burning towards it and it's clearly cracked.

So I bust out the soldering iron, and remove the busted ass component. Plug it back in, and FUCK YES, STARTS UP!

Now what I try I can't get into the web interface (says 192.168.1.254 in the manual). and what bothers me more is serial doesn't work.

Now the way I do serial is via my big guy vm server which is one of the only serial ports I have. I use screen on the tty0 in /dev. Now I tried all the different speeds, hitting enter a lot. Even trying when it's booting up etc etc. I know this works because I can connect to the device in the next paragraph (I installed console pfsense image like a boss).

I also realized that my little router that I have that has a RJ45 serial port, could on the other end of the cable maybe connect to a RS232 style port. Since it's PFSense I tried the "cu" command to no avail.

tl;dr:

Got this defective router "as-is" (and I fixed it, by removing a defective surface mount tiny capacitor on the POE Daugherboard). It passes traffic fine, but no web interface nor serial. It also seems to boots fine too (status flashes fast whilst booting and then goes solid). Tried from a proper hardware serial port connecting via screen on /dev/tty0. Also tried from a tiny atom router pc's rj45 serial (to standard serial), using freebsds cu command (it's a pfsense router).

finishing notes:

All I get is nothing. Hitting enter doesnt work. changing speeds etc. Update firmware somehow? Tried reset, and rebooting etc. Nogo. I downloaded the latest firmware, can I setup a TFTP server with certain settings to get this to auto update? If I have to I can buy a serial to usb adaptor so I can try this in windows, or use yet another machine.

Also the last little thing, is I haven't replaced the surface mount cap yet. I really don't think that's important though (at least with this issue, it might affect PoE support etc, and maybe I am risking bad shit).