Unless President Trump is going to use the meeting to show Mueller what goods he has on him, then yeah this can’t be a good idea.
And under oath? He should insist on the same treat HRC got — no oath, no recordings, no notes.
This matters:
“he would be willing to answer questions under oath, but not until after asking whether Hillary Clinton, his 2016 campaign rival, has spoken under oath to the F.B.I. in the investigation into her use of a private email server while she served as secretary of state”.