So it sounds like the ONE Time they see something like this, the second camera used to verify the sighting is down?
Boy - those aliens ARE sneaky!
The budget for this must be ****, wildlife cams would probasbly work, and some of the best sellers on Amazon are under $100 (with night vision). Even a couple of ordinary webcams (thrift stores, etc) inside a weatherproof container of some sort could be live-streamed to a local hard drive.