access 2k13 vba concatenate multiple items in openargs

have an existing report driven by a query that works fine. It has a single, openargs variable now. I would like to add an additional variable to the openargs string for some other work on the report. I understand that I have to parse the openargs  variables.

The query that drives the report is:
SELECT MACHINE.MACHINE, MACHINE.DESCRPTION, MACHINE.REG, MACHINE.PICTURE AS PIC, MACHINE.RPM, MACHINE.POINTS, MACHINE.CLIENT_ID, MACHINE.PHOTO, TRENDMAC.SET_DT, TRENDMAC.ACRONYM, TRENDMAC.RATING, TRENDMAC.SUMMARY, MACHINE.COMMENT, TRENDMAC.CHECK_NEXT, MACHINE.HORSE_PWR
FROM (MACHINE LEFT JOIN (SELECT TRENDMAC.MACHINE, Max(TRENDMAC.SET_DT) AS SET_DT FROM TRENDMAC IN 'G:\CAC\DB\PLANT\v6'[dBase IV;] WHERE TRENDMAC.RATING NOT LIKE "N" and TRENDMAC.RATING NOT LIKE "X" GROUP BY TRENDMAC.MACHINE)  AS SubQuery ON MACHINE.MACHINE=SubQuery.MACHINE) LEFT JOIN TRENDMAC ON (SubQuery.MACHINE=TRENDMAC.MACHINE) AND (SubQuery.SET_DT=TRENDMAC.SET_DT) IN 'G:\CAC\DB\PLANT\v6'[dBase IV;]
WHERE MACHINE.DUMMY=False
ORDER BY MACHINE.MACHINE;

the command to run the report is:
    DoCmd.OpenReport "Field Notes", acViewReport, , , acHidden, Me.ACRONYM

what I'd like to do is put an additional variable (set_dt) from the query into the openargs something like this:
... , me.acronym & "|" & me.set_dt

currently doesn't pickup the set_dt field, I get null instead