Hi!
Well, I honestly don't think a hardware fix can help either. The (regular) hardware fix will only bypass the reset signal. That means that if the Amiga boots the card is reconized immediately. And in your case it even that the Amiga won't boot. Odd!
My suggestion is that you boot the Amiga, without the network card and as soon as the Amiga is booted, you insert the card. See what happens then!
I know it's a sin, but this was the only way for me the let my Amiga reconize the card. Sometimes it did'nt even reconized it at once, so I had to re-insert the card again.
See if works. If your Amiga freezes when you insert the card i suggest a different card.
If it DOES work, you can contact me for a regular hardware fix. I use to supply these for "various" Amiga suppliers.