edit: fixed, off the market!
Hello : Bummer you are having so much trouble I've been there many times, may be I can help. I have a working Color Turbo ADB Motherboard that Brian repaired for me that I would be happy to make you a deal on I think $150 would cover the costs and is a fair price as it has new caps and works!
I also know I have a Turbo Color Motherboard I have not tested but it looks well kept and if she works, I'll offer it to you for $100 this is well under market value , I empathise with what you have been going through just trying to help...
I also have a lot of standard NeXT Color motherboards one of these how about $20 and shipping or a new old stock one ... $100 but they are only non adb compatible again it means you would need to have NeXT non adb components...
it is a battle to keep them going but my heart is in it.
So if you do give it away or decide to keep it, I'll try and help either way. I have family in Chillawack so if no takers let me know and I'll see if they can pick it up. I would prefer helping you get it running or a forum member get this one ;)
*****Update: Awesome I hope the replacement board does the trick , invoice is sent.