Hi @sampl! Welcome to the forum 
Yes, this is certainly possible in Retool. One option is pulling in the values needed from both collections, and then using a query within Retool to join them. Here's a general outline of this:
Have a getUsers query which runs on page load, and on success triggers our getOrgs query:
Then our getOrgs query which triggers on success our join query:
Then finally our join query, which uses SQL syntax to join the json objects:
Then we can set our table to be the result of this join query:
