Somewhere around here there are detailed instructions on how to engrave objects more than 0.5" in height but less than 2.0". I’ll let another person find the instructions.
But using gross approximations… You want to get the top surface of the object to be engraved no more than 0.5" above the honeycomb of the crumb tray so that it falls within the focus range of the laser head lens. For an object 0.69" high that means you must remove the crumb tray and raise the object somehow. But you still need the top surface of the material to be within the range.
The crumb tray on most units is about 1.4" tall. So that means you want an object to fall no more than 0.5" above that or, between 1.4" and 1.9" above the floor of the unit (approximately). If you remove the crumb tray and put something under your bottle openers that is 1" tall that will place the top surface of your bottle opener at 1" + 0.69" = 1.69". That is pretty much in the middle of the limits I quoted before. A pretty good place to be.
Use the set focus feature so that the unit can find the exact height of the bottle openers. That all there is to it.
Figuring out settings for non proofgrade material always requires testing. But I would just use the settings for proofgrade cherry hardwood as a good first test.