The other possibility is that the lawyer was lying. And this is the version the Secret Service is claiming, as they say they never vetted the meeting.
The lawyer, in his zeal to establish that there was nothing nefarious about the meeting, apparently forgot that if he claimed that the USSS vetted the meeting, it would be assumed that either Donald or Melania attended the meeting, as they were the only ones protected at the time.
We already know that Trump Sr. was in the Trump Tower for most of the day June 9. Did he actually attend the meeting, which also took place in Trump Tower? Theoretically possible, but so far we have no evidence of that. Still, I’d really like to know where Trump Sr. was at the time the meeting was going on, and if there are any credible witnesses who can back that up.