I don't know how much might be owned by other ETFs. I only reported on numbers where I could find reported data. I listed my sources. If you can find some reports of vault totals for other ETFs, please let me know!
I posted vault totals for the end of December 2024 and included a new source that lists and totals a multitude of ETFs holdings in the LBMA:

Silver Demand Drivers (and vault totals)
Update (see post #68 for last month):LBMA - As at end August 2024, ... There were also 26,245 tonnes of silver (a 1.4% decrease on previous month)... SLV report for 6 September claims 363.01 mtoz vaulted in London. That leaves a total of ~480.78 mtoz of silver in the London vaults not owned by...
Also - it looks like Trump's tariff threats are causing actors to move physical silver from London to USA. LBMA might get stressed as January rolls along...