Hey  
Looks like Issue 2 was fixed on https://folio-dev-spitfire-2nd-consortium.ci.folio.org/ , see attached screencast:

From and  
When user selects shared = Yes and held by = current_tenant then will see return shadow copies in current tenant
When user selects shared = Yes and held by = another_tenant then any shadow copies in that other tenant
When user selects shared = Yes and held by = central_tenant then Not Possible
When user selects shared = No and held by = current_tenant then no shadow copies are returned and only local records that have holdings
– Exception is browse by subjects and contributors as it will return all local records
When user selects shared = No and held by = another_tenant then NOT possible
When user selects shared = No and held by = central_tenant then NOT possibleBrowse by subjects and contributors

• Shared by behavior - only check instances

  • Default behavior (no selection) Show all subjects or contributors from both shared instances and local instances for current tenant

    • Number of titles = Shared + Local instances for current tenant-- When user selects shared = Yes then see all subjects or contributors from all shared instances

    • Number of titles = Shared instances-- When user selects shared = No then see all subjects or contributors from all local instances for current tenant

    • Number of titles = Local instances for current tenantCentral tenant will not have the Shared by facet on browse subjects, contributors, and call numbers AND search too (Inventory app)
      Central tenant will not have the Shared by facet on browse authorities and search authorities (MARC authority app)

  • For browse by subjects and contributors >> Held by behavior = only check instances. WILL NOT DO FOR POPPY RELEASE*

Re-tested on Spitfire Consortium rancher environment:
Issue 1 fixed, see attached screenshot:

Another issue-2 appeared:
"shared" facet doesn't work for Browse by Contributors/Subjects when shared Instance has "shadow" copy on current tenant.
Scenario:
1) Shared Instance with contributor/subject has "shadow" copy on "University" tenant
2) Local Instance with contributor/subject exists on "University" tenant
3) Send GET request "/browse/contributors/instances?query=(name>="contributor" or name<"contributor") and {}instances.shared==false"
4) Send GET request "/browse/contributors/instances?query=(name>="contributor" or name<"contributor") and {}instances.shared==true"
Expected result: 
For step 3 - only local Instance record is returned in response.
For step 4 - only shared Instance record is returned in response.
Actual result:
For step 3 and 4 - both (local and shared) instance records are returned in response.
See attached screenshot:

According to discussion with PO: previously described scenario works as expected, because contributors/subjects from local Instances regardless of whether the member institution has holdings will be displayed in "Held by" facet options and could be found by browsing with applied "Held by" facet.

One issue to be fixed:
"Number of titles" found in response should include only Local Instances and Shared Instances (which has Holdings) when browse executed from member tenant and same tenant is selected in the "Held by" facet.
See attached screenshot:
1 record is Shared
1 record is Local
Both records don't have Holdings
My request: {{host}}/browse/contributors/instances?query=(name>="Creelman, James Ashmore" or name<"Creelman, James Ashmore") and instances.tenantId==college

Tested on https://folio-dev-spitfire-2nd-consortium.ci.folio.org/ with following test data (see issues described in 2 and 3 steps):
Only 1 Instance record has "Holdings" on Member tenant ("College" tenant), see screenshot:

1. Sent GET request "/search/instances/facets?facet=holdings.tenantId&query=id=*" to see possible "Held by" facet options for Search by Instances. - looks like it's expected, I've received only one option for "Held by" facet, because only one "Holdings" was created (second screenshot)

2. Sent GET request "/search/contributors/facets?facet=instances.tenantId&query=name=*" to see possible "Held by" facet options for Browse contributors.
   Actual result: list of all tenants (institutions) names is displayed as options for "Held by" facet (third screenshot)
   Expected result: only 1 tenant (institution) name ("College") is displayed as option for "Held by" facet

3. Sent GET request "/browse/contributors/instances?query=(name>="C410756 Contributor Shared MARC" or name<"C410756 Contributor Shared MARC") and instances.tenantId==college" to receive browse contributors result list with applied "Held by" facet ("holdings.tenantId" can't be sent in this request). -
   Actual result: 88 records are returned to the response
   Expected result: only one record is returned in response, which I've created.