I think I saw yas bet that open recently have such program, 'deposit minimum $10 to get $200 welcome bonus'.

are you sure?
He misinterpreted the $200 bonus, $200 is the maximum bonus that can be obtained from 100% of the money deposited and $10 is the minimum deposit if you want to get a 100% bonus, can be found here
I only know that duelbits sometimes give freebets but that has been done for quite a while now, now they are giving boost odds promos more often, or OP can check roobet several times gave bet refunded on some matches