I'm giving an honest answer based on my personal experiences. The last few tours we took were only $400-$450/hr and I tipped $300-$400. If the hourly rate is now $700, then $500 to $650 is a fair amount to me. I don't consider myself a generous tipper ever.
Historically, 10-20% was suppose to represent a fair pay for somebody working in tipped position. These CM are earning a fair hourly (not a tipped) wage and nearly $1,000 tip is way excessive for the service performed.
If you’re feeling generous and want to leave a $1,000 trip to the CM or your favorite waitress, that’s an incredibly nice gesture on your behalf.
But let’s not pretend it’s the standard. I’d handily bet that most guests don’t tip their tour guide at all.