Pair a new iPhone to existing Dexcom G6

My daughter is running a Dexcom G6 with an iPod touch as the display device as well as using WiFi to share her reading with us (the original receiver was stepped on by another kid about 2 days after we got it). We have had success with this set up but as summer camp approaches, we need to have her run an iPhone since WiFi won’t be available. Is there a way to bring the iPhone in while still using the iPod for this session? She still has 8 days to go on this session and while I can get the transmitter SN from the iPod, I don’t have the number or label from the last applicator. I tried just pairing it but the iPhone won’t seem to pair with the transmitter and I didn’t know if it was because it was already paired with the iPod. I know you can pair the original display device and then bring another phone or iPod into the mix but I wasn’t sure about 2 “non-Dexcom” devices at the same time. Does anyone have any experience with this?
Thanks in advance and sorry for such a long post.