I guess it'll depend on wether or not you saved the session token. If you have the session token, you should be able to contact chipmixer and ask them to extend your session, and pick it back up when the DDos attack is finished.
Personally, i'd never deposit a single satoshi before saving the session token. In the pre-chipmixer days, when using bitmixer.io, the first thing i did before depositing anything was saving their letter of guarantee, which is the closes equivalent to saving the session token (AFAIK)