I don’t think it was “follow suit” by Pence.
If you watch Melania’s glance, she is either (looking to?) verifying the “signal” or prompting Pence to complete the “signal”. I’ll need to go back and watch Pence’s eyes and listen to the conversation around this movement.
Could be nothing at all but is an intersting confluence of glances and movements keeping in mind “watch the water”.
Watch the water has also come into play previously. There was some discussion about a bottle of Fiji, once. Also, IIRC, another one about his taking a “swig” during a pause in a speech.
I don’t see that from Melania at all.
I think when Q fans have no idea how to interpret a crumb, they come up with bizarre ideas to fill the void.