Mostly there is also a Jumper available on the motherboard so you can enable / disable the PS/2 mouse port.
If i where you, i should look for that jumper if it is available and working.. Then just enable the jumper end see in de bios program if it is enabled or not.. If it is, you should definitely solder an header on the place where there need to be one. Otherwise looking who can soldering it for you went you dont have the skill to do.
If the enable / disabled part is locked in the bios, then it really should be hard to get that working (then you need to have experience on modding bios roms)
~ At least it can do black and white~