Instead of setting the model to the UI5 core try setting it to the view like below:
this.getView().setModel(oModel, "model1");
In your view:
<Page title="{model1>/greeting}">
Instead of setting the model to the UI5 core try setting it to the view like below:
this.getView().setModel(oModel, "model1");
In your view:
<Page title="{model1>/greeting}">