I don't think Tesla has control over them, but it also probably doesn't matter much in practice for two reasons:
Firstly, the totality of resale value guarantees only represent about $139m in value for the next year:
"Subsequent to June 30, 2016, this program is available only in certain international markets. Resale value guarantees available for exercise within the 12 months following June 30, 2018 totaled $139.3 million in value."
... and that would be direct sales and third party leases.
Secondly, the vast majority of resale value guarantees expire without being exercised:
"Through 2017, we only had an insignificant number of customers who exercised their resale value guarantees and returned their vehicles to us. Based on current market demand for our vehicles, we estimate the resale prices for our vehicles will continue to be above our resale value guarantee amounts."
I.e. the current approx $674m of resale value guarantee liabilities on the balance sheet are listed at 100% per GAAP, but in reality represent an effective liability of less than 5% of that.
I.e. Tesla is applying inventory reduction measures that BMW and Volkswagen is performing too at the end of their quarters, which carmakers do in part to recognize more revenue, but also to gain a margin-leveraged cash flow advantage from reducing inventory at the end of the quarter.
Here's a graph showing how BMW does end of quarter inventory management, the fluctuation is significant, BMW sales volume goes up by about 30% before quarter end, most likely due to inventory push measures by dealers.
Tesla has much higher gross margins than other carmakers so the cash flow advantage from managing inventory at the end of quarters is even bigger. Them doing this could have a potential upside for Q3 cash flow.