Creating a list of years using bins with SQL BigQuery - sql

Question

I am working on a project that involves studying the impact of NFL executives. I am using ProFootball Reference tables for each team like this and I am trying to combine them with this table featuring the executives. As you can see, the two data sets are not matching, which has created problems. My first instinct was to isolate the executives from each team and use a CASE statement to manually enter them into each team's table, but since there are 32 teams, I want to avoid doing this manually if I can. I also figured this would not be possible if I did this as a career, so I wanted to do this with a SQL function.
I decided to create a bin where I would list out each year and then join, but first I needed to see if it would work with just the general managers.
I'm using BigQuery Sandbox and currently don't have access to anything with more permissions, so I don't have the permission to CREATE TABLE, unfortunately. I attempted to convert the executive table into one where each year is shown with each executive and attempted a pivot so that the split teams are converted into columns after I seperated the array. I opted out of the Pivot since there it seemed to want an aggregate value, but I am still running into a snag.
WITH bin AS(
SELECT *
FROM UNNEST(generate_array(1921, 2022, 1)) AS year),
gm_teams_cowboys AS(
SELECT
Name,
team,
came,
went,
FROM (
SELECT
Positions,
Name,
exec.From AS came,
exec.To AS went,
SPLIT(Teams, ',') AS team
FROM lyrical-star-357613.nfl_stats.nfl_executives AS exec)
WHERE Positions LIKE '%General Manager%' AND team LIKE '%Cowboys%')
SELECT
*
FROM gm_teams
LEFT JOIN bins
ON bins.year = gm_teams.came
This code also did not work in that it did not provide the columns I wanted, so I was wondering if there was a good way to do this that I was missing. Would I need to just suck it up and manually put the GMs and Owners in if I don't have the ability to create a table?