Hi eone
Just wanted to provide some additional feedback; installing the TPLink wifi adapter thetechguy suggested worked perfectly! Computers that could not connect to bots in ad hoc mode connect successfully using this adapter.

If you use this adapter, you might find it useful to install the configuration utility as well as the drivers. This allowed me to specify the TPLink as being dedicated to the bots, so the other unit's wifi adapter could connect to the router for internet access.

Thanks ttg!

DMS