Note that at this point, the OA-FROM keyword is just setting the OA
temperature for the borrowing system to the return air temperature for
the lending system. It isn't really modelling DOAS yet. The issue this
leads to is the heat recovery device is seeing the exhaust air stream
temperature from the dummy zone, not the borrowing zones.

In heating dominated climates, this can be overcome by either adding a
dummy internal load to the dummy zone to give it a higher return air
temp for heat recovery or what I do is use the frost control to force
the exhaust air stream temperature up to a reasonable value (73F) and
put that as electric heat on a separate, free meter. In a cooling
dominated climate, I don't know how you would force that dummy zone
return temperature down.

You can add a latent internal load too. For cooling - I think if you assign a negative value to the internal source that should work. The challenge is to get the scheduling correct for the load.

As a side note (if your DOAS is supplying neutral air - ignore this) - if you are supplying air that is significantly cooler than setpoint temperatures (60 degrees & cooler would probably qualify) you need to represent the cooling effect of the DOAS air into the room. You can do this with a negative internal load in the space with an assigned schedule too.

Vikram Sami, LEED AP BD+C