Google Sheets- building Dynamic Array with multiple IMPORTXML requests-CodePudding

I've got a complex (at least to me) xmlimport query - thanks to player0 from this question: (

now to implement checkboxes we can do:

=INDEX(SUBSTITUTE(TRIM(SPLIT(FLATTEN(SPLIT(QUERY(IFNA(
 CHOOSE(MATCH(MOD(SEQUENCE(999)-1, 9), {0, 1}), "♦", )&QUERY(TO_TEXT(
 {IF('Client Ads Served'!A2=TRUE, IMPORTXML('Client Ads Served'!H2, H6), );
  IF('Client Ads Served'!A3=TRUE, IMPORTXML('Client Ads Served'!H3, H6), );
  IF('Client Ads Served'!A4=TRUE, IMPORTXML('Client Ads Served'!H4, H6), );
  IF('Client Ads Served'!A5=TRUE, IMPORTXML('Client Ads Served'!H5, H6), );
  IF('Client Ads Served'!A6=TRUE, IMPORTXML('Client Ads Served'!H6, H6), )}),
 "where Col1 is not null", )&
 CHOOSE(MATCH(MOD(SEQUENCE(999)-1, 9), SEQUENCE(9)-1), 
 "♠","♠","♣","♣","♠","♣","♣","♠","♠")),,9^9), "♦")), "♠")), "♣ ", "/"))