I'm driving the ADuM260N from an FPGA that can source up to 3mA. Would 10k resistors from VIA-VIF to GND improve signal integrity when the signal is in the MHz range, or are there other factors to consider with the ADuM260N?
The inputs on the ADuM260N are high impedance CMOS inputs. They don't need resistors in front of them. Adding series resistance close to the FPGA outputs may be useful for emissions purposes though. A resistor and the trace capacitance will filter the higher frequencies from the edges, but 10kΩ sounds high.
Is there a specific problem you are seeing in an application?