@j_r,
As per the comments, this should work with a single search.
<form>
<label>Destination</label>
<fieldset submitButton="false">
<input type="dropdown" token="start">
<label>Start</label>
<fieldForLabel>Destination</fieldForLabel>
<fieldForValue>Destination</fieldForValue>
<search>
<query>|makeresults|eval Type="X,Y,X,Y",ID="1,1,2,2",Destination="A,B,C,D" |makemv Destination delim="," | makemv Type delim="," |makemv ID delim="," | eval x=mvzip(mvzip(Type,ID),Destination)|fields x| mvexpand x|eval x=split(x,",") |eval Type=mvindex(x,0),ID=mvindex(x,1),Destination=mvindex(x,2)|fields Type,ID,Destination|fields - _time
|rename C as "Search above is data generation"
|eventstats values(Destination) as TheOtherDest by ID | mvexpand TheOtherDest |where Destination!=TheOtherDest
|dedup Destination</query>
<earliest>-1s</earliest>
<latest>now</latest>
</search>
</input>
<input type="dropdown" token="dest">
<label>Destination</label>
<search>
<query>|makeresults|eval Type="X,Y,X,Y",ID="1,1,2,2",Destination="A,B,C,D" |makemv Destination delim="," | makemv Type delim="," |makemv ID delim="," | eval x=mvzip(mvzip(Type,ID),Destination)|fields x| mvexpand x|eval x=split(x,",") |eval Type=mvindex(x,0),ID=mvindex(x,1),Destination=mvindex(x,2)|fields Type,ID,Destination|fields - _time
|rename C as "Search above is data generation"
|eventstats values(Destination) as TheOtherDest by ID | mvexpand TheOtherDest |where Destination!=TheOtherDest
|search Destination=$start$
|dedup TheOtherDest</query>
<earliest>-1s</earliest>
<latest>now</latest>
</search>
<fieldForLabel>TheOtherDest</fieldForLabel>
<fieldForValue>TheOtherDest</fieldForValue>
</input>
</fieldset>
<row>
<panel>
<title>Data</title>
<table>
<search>
<query>|makeresults|eval Type="X,Y,X,Y",ID="1,1,2,2",Destination="A,B,A,B" |makemv Destination delim="," | makemv Type delim="," |makemv ID delim="," | eval x=mvzip(mvzip(Type,ID),Destination)|fields x| mvexpand x|eval x=split(x,",") |eval Type=mvindex(x,0),ID=mvindex(x,1),Destination=mvindex(x,2)|fields Type,ID,Destination|fields - _time
|rename C as "Search above is data generation"
|eventstats values(Destination) as TheOtherDest by ID | mvexpand TheOtherDest |where Destination!=TheOtherDest</query>
<earliest>-1s</earliest>
<latest>now</latest>
</search>
<option name="drilldown">none</option>
</table>
</panel>
</row>
</form>
... View more