I figured it out, had to use the window function on each stream to create another timestamp column. Then could do a non-equality inner join based on the two colums.
Then create a window column called
coalesce(lead(Timestamp_Req), toTimestamp('9999-12-31 23:59:59', 'yyyy-MM-dd HH:mm:ss'))
Which will give output that looks like this:
Then I created a derived column that took one second off the TimestampEnd column,
TimestampEnd_P - seconds(1)
Next, do the same process for the other stream.
Lastly, do the inner join on the two streams. Keep in mind you will have to broadcast one of these - try to broadcast pick the stream you think will be smaller.
Then create a derived column called time_stamp or whatever that combines the two time series:
iif(Timestamp_Req > Timestamp_P, Timestamp_Req, Timestamp_P)
Lastly do a select to remove all the extra timestamp columns only keeping the derived col that was jsut created.