Maybe we can get a body language expert to examine his response for the tale-tell signs of a LIAR.
The wording is significant when a liar tells a whopper ... ‘that’s absolutely true’. It’s kind of like the used car salesman using ‘I’ll tell the truth’ or ‘To be completely honest with you ... and then the bog lie is proffered. Notice too that the liar-in-chief immediately misdirected his young dupes, just in case one or two were savvy enough to ask a follow up which might stump him.