In regards to validator nodes, they'll basically be like an L2 on HIVE and my understanding is they'll reconcile whatever tokens are not actively in use on HIVE to the reserve wallet which will then essentially escrow tokens that are not in circulation on HIVE but on other chains.
Part of the problem with coin tracking sites is they were set up a long time ago and the information isn't accurate. Part of updating them is giving them correct reserve wallets to correct circulating supply information. Essentially they'll be reconciling circulating supply on all chains to get an actual circulating supply. Have to finish clean up to submit correct info.
So every chain will have 3 billion tokens basically. Whatever isn't in use/circulation on the chain will be in a reserve wallet. Having all the tokens minted and properly managed and accounted for is better optics for the contract. Essentially there will be no further token minting.
I'm not super familiar with the Terablock setup. They have contracts and funds on the 3 chains we're currently operating on. They escrow funds on one side and release on the other. The amount of tokens they have isn't really very much, in the single digit millions iirc off the top of my head. Theoretically they could get way too one sided, like say 5 million on BSC and 100k on their BSC counter wallet on HIVE and could have to request more funds to provide liquidity. That's my best ELI5 understanding, but I haven't personally spoken to Terablock as that was all setup before my time.