@Timothy Leavitt , thank you for your help!

After clearing out the cached data from TestCoverage with the 

Do ##class(TestCoverage.Utils).Clear()

command, and Setting the following tCoverageParams subscripts, 

SET tCoverageParams("ProcessIDs") = "*"

SET tCoverageParams("CoverageDetail") = 0

then it works.

I'm calling
TEST-EHR>DO ##class(TestCoverage.Manager).RunTest(,"/nodelete",.tCoverageParams)

my tCoverageParams are the following.  

TEST-EHR>zw tCoverageParams
tCoverageParams("CoverageClasses")=$lb("modul.ehr.host.check.CheckOperation","modul.ehr.host.docadd.EHRAddOrUpdateOperation")
tCoverageParams("CoverageDetail")=3
tCoverageParams("SourceNamespace")="TEST-EHR"
tCoverageParams("Timing")=0

TEST-EHR 4d1>w $zv
IRIS for UNIX (Red Hat Enterprise Linux for x86-64) 2021.1 (Build 215U) Wed Jun 9 2021 09:48:12 EDT
TEST-EHR 4d1>w $zu(56,2)
$Id: //iris/2021.1.0/kernel/common/src/aclass.c#1 $ 13260 0