Upgrading Bluetooth to support Airdrop help.

I have had a success installing a BCM94331PCIEBT4CAX in my 2009 Mac Mini, but there is an issue. The antennas do not fit on the newer card and using the mac mini without them results in a slower WiFi connection and bluetooth being useless. For example airdrop now works on it BUT it will not detect any device or be detected (for example your iPhone) to send files or photos unless you put your device on top of the Mac Mini. So my question is what can I do. I have an idea on buying a new set of antennas that are compatible, but I cannot find any information on if it fits my needed card. If someone knows what I can do to get some compatible antennas so I can make the range normal again it would be a huge help.