Creating a new fermata symbol

In a piece I’m currently writing there is a section in free meter time, where I wanted to write independent fermatas in between passages or notes (see attached example).
With Finale- a program so inferior to Dorico I cannot believe I made the switch only this year- the solution was easy: hide a rest, create a fermata symbol, put symbol where the rest was, voilà. Here on Dorico I cannot find a way or a workaround to what I am looking for. Could someone please help?
Also, bonus question: Is there a way to write a fermata only for one instrument, without it appearing on all staves of the score?
Many thanks!

Create a Playing Technique with the Fermata symbol. You can move it into place in Engrave mode.

This also answers the bonus question.

Thank you!