Frankly, I didn't think much about how to organize posts, I reported just easy technical method.

It can be some "magick" address, or special googlable words (e.g. "hmwyda_eth_russia"), or you can try to find ETH text search engines (e.g. https://ethereum.ms but it doesn't work very well).

The more important - you don't completely understand the idea. Agents do not contact to donors.
https://memo.sv/post/84862ff1a0e58764272ae8c3cc8f199412270e557fa6040b7541c61bba28df4e
https://memo.sv/post/589870f1d876df68df3fdb7ed077d6511103101637eb98d4edffb2fa8501cd3e