There is nothing wrong with RLGz address, that's a miner.
I think these are coins that were abandoned from disabled Poloniex users who did not complete KYC before the deadline. IMHO they are as good as burnt coins. Some people speculate Circle/Goldman sachs could dump them in the future all at once, but that would be illegal so it's very unlikely.
The time of rewards are strange, as well the block heights
Block Height Date/Time Age Difficulty Reward
1108494 2019-06-15 02:36:10 7 minutes 1199.0 22.66666666 RIC
1108494 2019-06-15 02:36:10 7 minutes 1199.0 22.66666666 RIC
1108493 2019-06-15 02:34:25 9 minutes 1199.0 22.66666666 RIC
1108493 2019-06-15 02:34:25 9 minutes 1199.0 22.66666666 RIC
1108488 2019-06-15 02:27:41 16 minutes 1199.0 22.66666666 RIC
1108488 2019-06-15 02:27:41 16 minutes 1199.0 22.66666666 RIC