Transfer calls outside of stasis app to a bridge using ARI

I need this scenario:

A wants to talk to B, so he calls [b]O /b. O puts him on hold and then calls B and asks him if he wants to talk with A. If he does, the operator connects them immediately and hangs up, so now A and B are talking together. A should be able to make calls from any client, in this case Zoiper.

The idea was that the operator uses web application which uses ARI. So, if I create two internal SIP channels with ARI and create a new bridge, and add those channels to it - that works. Both users can talk to each other and that is perfect. But that only works if I create channels with ARI. If user A calls user B with Zoiper, and I try to add one of them to a new bridge with ARI, I get the following error: “Channel not in Stasis application”.

Also, if I try to add a channel created with ARI to a bridge created outside of ARI (Zoiper) I get the error that the bridge is not in Stasis application.

I followed this article and added the following lines in extensions_custom.conf

[myApp] exten => 1,1,Noop() same => n,Stasis(myApp) same => n,Hangup()

Can anyone help me, I don’t understand Stasis, how can I set up everything and which methods on ARI should I use to join two channels (one created with Zoiper, the other with ARI)? Thanks