SQL Server Distributed queries with Teradata - sql-server

Question

I am trying to get distributed queries to run on SQL Server 2012 with a linked server to Teradata.
Connection works fine and query returns quickly if I pass the where clause into the remote SQL using openquery e.g.
select *
from openquery(td, 'select * from lib.purchases where z_PO = ''123456''')
However the below does not run as expected: SQL Server loads the entire table and performs a local filter:
select *
from openquery(td, 'select * from lib.purchases') where z_PO = '123456'
The source table has 100M records.
Obviously index play no role here as query runs just fine on TD side.
What I have tried:
sp_configure 'Ad Hoc Distributed Queries', 1
set Collation Compatible" = True on the linked server properties
Instead of 2, set Collation Name = Latin1_BIN to match (closely?) TD character set (ASCII).
Not sure collation is the issue as I get same result when filtering on numeric fields.
Somehow the so-called query optimizer in SQL Server does not push simple filtering down to the remote server.
Is this the ODBC driver's fault (using 16.10) - a setting, a bug? SQL Server 2012 (v11.0.6248.0) setting I am missing (or path req'd)?
Below is the OLEDB for ODBC properties that I capture in SQL Profiler:
<ProviderInformation>
<Provider>MSDASQL</Provider>
<LinkedServer>td</LinkedServer>
<ProviderCapabilitiesAndSettings>
<Ansi92EntrySupport>0</Ansi92EntrySupport>
<ODBCCoreSupport>1</ODBCCoreSupport>
<ODBCMinimumSupport>1</ODBCMinimumSupport>
<SimpleGrammarSupport>0</SimpleGrammarSupport>
<AnsiLikeSupport>0</AnsiLikeSupport>
<SQLLikeSupport>1</SQLLikeSupport>
<DateLiteralsSupport>0</DateLiteralsSupport>
<GroupBySupport>0</GroupBySupport>
<InnerJoinSupport>0</InnerJoinSupport>
<SubqueriesSupport>0</SubqueriesSupport>
<SimpleUpdatesSupport>0</SimpleUpdatesSupport>
<HistogramsSupport>0</HistogramsSupport>
<ColumnLevelCollationSupport>0</ColumnLevelCollationSupport>
<ConnectionSharingSupport>0</ConnectionSharingSupport>
<MultipleActiveRowsetsSupport>0</MultipleActiveRowsetsSupport>
<MultipleResultsSupport>1</MultipleResultsSupport>
<AllowLimitingRowsReturned>1</AllowLimitingRowsReturned>
<NullConcatenationYieldsNull>0</NullConcatenationYieldsNull>
<StructuredStorageAccessToLargeObjects>1</StructuredStorageAccessToLargeObjects>
<MultipleConcurrentLargeObjectSupport>0</MultipleConcurrentLargeObjectSupport>
<DynamicParametersSupport>1</DynamicParametersSupport>
<NestedQueriesSupport>1</NestedQueriesSupport>
<IndicesAvailableAsAccessPath>0</IndicesAvailableAsAccessPath>
<AllowDataAccessByReference>1</AllowDataAccessByReference>
<RowsetChangesAreVisible>0</RowsetChangesAreVisible>
<RowsetSupportsAppendOnly>0</RowsetSupportsAppendOnly>
<UseLevelZeroOledbInterfacesOnly>0</UseLevelZeroOledbInterfacesOnly>
<RowsetUpdatability>1</RowsetUpdatability>
<AsynchronousRowsetProcessingSupport>0</AsynchronousRowsetProcessingSupport>
<DataSourceUnicodeLocaleId>0</DataSourceUnicodeLocaleId>
<DataSourceUnicodeComparisonStyle>0</DataSourceUnicodeComparisonStyle>
<DataSourceCollationComparisonFlags>0</DataSourceCollationComparisonFlags>
<DataSourceCharacterset></DataSourceCharacterset>
<DataSourceSortOrder></DataSourceSortOrder>
<DataSourceNullCollationOrder>4</DataSourceNullCollationOrder>
<CurrentDbCollationSameAsDefaultRemoteDbCollation>0</CurrentDbCollationSameAsDefaultRemoteDbCollation>
<UnicodeLiteralSupport>0</UnicodeLiteralSupport>
<UnicodeLiteralPrefix></UnicodeLiteralPrefix>
<UnicodeLiteralSuffix></UnicodeLiteralSuffix>
<DateLiteralPrefix></DateLiteralPrefix>
<DateLiteralSuffix></DateLiteralSuffix>
<ObjectNameConstructionFlags>54</ObjectNameConstructionFlags>
<SchemaSeparator>.</SchemaSeparator>
<CatalogSeparator>.</CatalogSeparator>
<QuoteSeparator>"</QuoteSeparator>
<BitRemoting>0</BitRemoting>
<UnicodeLiterals>0</UnicodeLiterals>
<ProviderOledbVersion>131072</ProviderOledbVersion>
<HalloweenProtectionNeeded>1</HalloweenProtectionNeeded>
<RowsetUsableAcrossThreads>0</RowsetUsableAcrossThreads>
<ObjectNameIsSinglePart>0</ObjectNameIsSinglePart>
<Cardinality>-1</Cardinality>
<BookmarkSupport>0</BookmarkSupport>
<BookmarksReusable>0</BookmarksReusable>
<TableFlags>0</TableFlags>
</ProviderCapabilitiesAndSettings>
and here the details of the column in the filter:
DBCOLUMNINFO>
<pwszName>z_PO</pwszName>
<pTypeInfo>0x0000000000000000</pTypeInfo>
<iOrdinal>53</iOrdinal>
<dwFlags>120</dwFlags>
<ulColumnSize>10</ulColumnSize>
<wType>129</wType>
<bPrecision>255</bPrecision>
<bScale>255</bScale>
<DBID>
<eKind>DBKIND_NAME</eKind>
<uName.pwszName>z_PO</uName.pwszName>
</DBID>
</DBCOLUMNINFO>
As a FYI, the context is wrapping the openquery, joined with local data, into a SQL Server view, which is the only thing users would see - from there, they can apply any filter (WHERE) within PowerQuery (XL) or PowerBI. A way to circumvent the lack of DirectQuery support through ODBC.