Withdrawals depend on the account where the funds were earned remaining active. If the trader loses the account, there is no way to receive the withdrawal or for the funds to be returned, as the account where the funds were earned no longer exists. 

Will I lose the funds if I lose the account?

Yes, and there is no way to avoid this.

Can the funds be returned to another account of mine? 

No, because each account has its own history, goals, and limits, and there is no way to transfer the funds from one account to another.