If you'd like to hide specific subscriptions for all of your users in My Account, you can do so by applying the following steps.
In the My Account Library Components template, find the line that starts with:
<tbody ng-repeat="libraryItem in collection | orderBy: 'resourceName' track by libraryItem.id ">
And replace it with this:
<tbody ng-repeat="libraryItem in collection | orderBy: 'resourceName' track by libraryItem.id" ng-if="libraryItem.rid != '<RID>'">
Please note, to replace <RID> with the actual resource ID of the subscriptions from your Piano application.
This will block showing items with this Resource ID in the My Account Library tab.