The dominant crypto exchange was hit by outflows amid revelations that rival FTX may have misused customer funds.
Mobius said he wouldn't invest his own cash or client money in digital assets as "it's too dangerous."
The former Trump spokesman wants to buy back a stake of his SkyBridge Capital from FTX.
Voyager had already joined several other crypto firms in restricting trading and withdrawals.
Bitcoin's gyrations underscore the uncertainty looming over cryptocurrencies.