Pure FUD. Solo blocks are not shared with pool miners. The finder (solo or pool)
gets the tx fees for the block they found. The pool has no control over this.
Internal transactions don't exist on the blockchain, the're just for accounting.
PPLNS has nothing to do with how much a block pays out, only how to split
the block reward among the pool miners, and only for blocks found by the pool.
Wait what? Pools can reject outside transactions when loading blocks on their node and instead load cheap 1gwei transactions. This is common knowledge. I'm not sure what the second half of your paragraph is talking about.