Heartbeat monitorind using iPad as Zwift Device

using an Apple Watch 4.0 connected to an iPhone X max as Zwift device, everything works fine.
with my iPhone connected via HMDI to a bigger TV screen is awesome.
using Stryd for Speed and Cadence, AW for HB


I want to use an iPad as Zwift device, bigger screen which is easier to operate during the run.
Stryd still works fine using an iPad
but how can i use the HB monitoring from my Apple Watch when Zwift is running on an iPad? it doesn’t see the watch for pairing as it is connected to my iPhone