Getting actual memory usage per user session in SSAS tabular model

Question

I'm trying to build a report which would show actual memory usage per user session when working with a particular SSAS tabular in-mem model. The model itself is relatively big (~100GB in mem) and the test queries are relatively heavy: no filters, lowest granularity level, couple of SUM measures + exporting 30k rows to CSV.

First, I tried querying following DMV:

select SESSION_SPID
,SESSION_CONNECTION_ID
,SESSION_USER_NAME
,SESSION_CURRENT_DATABASE
,SESSION_USED_MEMORY
,SESSION_WRITES
,SESSION_WRITE_KB
,SESSION_READS
,SESSION_READ_KB 
from $system.discover_sessions
where SESSION_USER_NAME='username'
and SESSION_SPID=29445

and got following results: $system.discover_sessions result

I was expecting SESSION_USED_MEMORY to show at least several hundreds of MBs, but the biggest value I got is 11 KB (MS official documentation for this DMV indicates that SESSION_USED_MEMORY is in kilobytes).

I've also tried querying 2 more DMVs:

SELECT SESSION_SPID
,SESSION_COMMAND_COUNT
,COMMAND_READS
,COMMAND_READ_KB
,COMMAND_WRITES
,COMMAND_WRITE_KB
,COMMAND_TEXT FROM $system.discover_commands
where SESSION_SPID=29445

and

select CONNECTION_ID
,CONNECTION_USER_NAME
,CONNECTION_BYTES_SENT
,CONNECTION_DATA_BYTES_SENT
,CONNECTION_BYTES_RECEIVED
,CONNECTION_DATA_BYTES_RECEIVED from $system.discover_connections
where CONNECTION_USER_NAME='username'
and CONNECTION_ID=2047

But also got quite underwhelming results: 0 used memory from $system.discover_commands and 4,8 MB from $system.discover_connections for CONNECTION_DATA_BYTES_SENT, which still seems to be smaller than the actual session would take.

These results don't seem to correspond to a very blunt test, where users would send similar queries via PowerBI and we would observe ~40GB spike in RAM allocation on the SSAS server per 4 users (so roughly 10GB per user session).

Have anyone used these (or any other DMVs or methods) to get actual user session memory consumption? Using SQL tracer dump would be the last resort since it would require parsing and loading the result into a DB and my goal is to have a real-time report showing active user sessions.