I'm having similar issue, I attached .popoverTip() to buttons, and the tips are controlled by TipGroup too, which is quite similar to what @lrreynolds did.
The code works fine in simulator, but when I'm testing on real device, the next tip didn't show up as expected after the tip before is dismissed, and displays popup as sheet for one time.
Another issue occurred in simulator (I didn't test in actual device) about .popoverTip() is that when I dismiss the tip by tapping other part of the screen instead of tap the dismiss button of the tip, the next tip didn't show up too. when I re-enter the app, the tip that was dismissed reappeared.
Either the TipKit is having problem or the iOS, because the simulator provided by Xcode isn't 100% identical to real device. Another example is that when you having NavigationStack inside DocumentGroup you will see two toolbar vertical stacked in simulator, but one overrides another in actual device, since it is not related to the current topic so I'm not going to talk too much about that.
I'm now watching this thread to see if anyone could find the cause or solution to this .popoverTip() and TipGroup issue.