Father in law just in motorcycle accident while working as driver for diagnostic emissions company. Insurance company calling him. What should he do

Company he works for tests emissions on exotic motorcycle for manufacturers that want to sell in the US. He is paid to put miles on the vehicles for certain testing thresholds (ei. 5,000 miles, 10,000 miles etc). While driving he was in an accident he claims was caused by a defect in the vehicle. He broke his tail bone and knee and sustained a variety of injuries and is now out of the hospital but bedridden (bought him hospital bed and taking care of him). He's getting calls from what I assume is Workman's Comp adjuster. What do you suggest he do?