Regarding the dependencies…
When compiling for v3.x it was notices that for some dependencies a specific version had to be used. This is from the Raspberry Pi code:
sudo apt-get update -y && sudo apt-get install -y libqt4-dev libprotobuf-dev libboost-thread1.62-dev libboost-program-options1.62-dev libboost-filesystem1.62-dev libboost-system1.62-dev
sudo apt-mark hold libqt4-dev libprotobuf-dev libboost-thread1.62-dev libboost-program-options1.62-dev libboost-filesystem1.62-dev libboost-system1.62-dev
And some specific packages installed:
wget https://github.com/cryptoBUZE/reddcoin/releases/download/rpi_raspbian_buster_v3.0.0/libssl1.0.0_1.0.1t-1%2Bdeb8u6_armhf.deb
wget https://github.com/cryptoBUZE/reddcoin/releases/download/rpi_raspbian_buster_v3.0.0/libssl-dev_1.0.1t-1%2Bdeb8u6_armhf.deb
wget https://github.com/cryptoBUZE/reddcoin/releases/download/rpi_raspbian_buster_v3.0.0/libprotobuf10_3.0.0-9_armhf.deb
sudo dpkg -i libssl1.0.0_1.0.1t-1+deb8u6_armhf.deb
sudo dpkg -i libssl-dev_1.0.1t-1+deb8u6_armhf.deb
sudo dpkg -i libprotobuf10_3.0.0-9_armhf.deb
You might want to try it again with these dependencies?
For Berkely DB, you could try the instructions on that from here: https://wiki.yavuzselim.nl/tech/tutorials/reddcoin-updated-staking-with-reddcoin-core-client-gui-wallet-on-a-raspberry-pi-model-3b/.
There is a part that describes “Download, unpack, configure, build and install Berkeley DB.”