The wife was all upset about this and I agree with her and everyone whom posted their view. And even those stating he can't take the fifth because of the pardon. And in actual true court room someone can in fact have a amnesty or pardon and still either refuse or invoke the 5th. The absolute worst that can happen is contempt or court/congress.
But this we still have to consider, everyone has the absolute right to invoke their Constitutional rights at ANY time.
Congress is NOT court, so yes even though they can attempt to compel testimony. They have limits, contempt of congress is about it. penalty $100,000.00 fine max and or up to 1 year in jail. Understand Congress cannot directly impose criminal penalties or final punishments itself for a contempt citation. It must go to criminal prosecution court.
So can he plead the 5th and get away with it yes.
And honestly I basically told the wife the same as
@Bowhntr6pt stated. Here is the absolute worst I can think of. Congress takes a vote for contempt of Congress, say it passes, then it "must" be referred to the DOJ to impose the penalties in a federal trial, He maintains the 5th, he winds up with a contempt of court conviction is a penalty of $1000.00 or 6 months imprisonment. The problem is that even if congress votes yes it still requires a court to convict. Could he wind up being convicted of both contempt of Congress and court if he maintains his 5th amendment protects yes, Highly doubtful, the problem lies in the fact that the fifth is absolute. most likely the court would dismiss the case.
truly it's a dog and pony show to give the concept that they (Congress) is attempting to do something about his actions.
Do I think he should face the music? absolutely, but our system protects of "should" protect everyone. Had it not been in the public eye and him not being in his position yeah they would throw the book at him. But with the dog and pony show yeah they have to follow the rule to a T which means he walk scot free.