there's only 3 input and 2 output, where address 1PNQDmVYFhofPSBZKonz8RKUhxSFUFrQnN used on both input and output which deviate from the common behavior.
There is no such common behaviour; when "new change addy" option was not opted, then either one of the input will appear in output as well.
Only in rare cases, exchanges/casinos will able to find exact inputs for a required output+fees for a transaction. In most cases, a change addy is needed and when "new change addy" option was not enabled then one addy will appear in both input and output.
You are missing the point here. It's not just about the change address. It's about the fact that you (or whoever was using that wallet at that time) used multiple input addresses, linked to different forum accounts, and combined them in the same transactions to send funds to addresses that are also part of the same wallet but used by other forum accounts. No exchange or casino, or any other custodial service for that matter, would do something like this.
And let's not forget that almost all of the related accounts were registered on the forum around the same time. That's another "coincidence" that's hard to ignore.
Honestly, you dug your own grave when you started this thread. Your best bet was to come clean and admit that you bought this account and have nothing to do with the previous owner. But you're too stubborn to do that. Instead, you're insisting that you're the original owner, which is just digging yourself a deeper hole. Given the connections between this account and other known scammers, cheaters and ban evaders, the negative tag is completely justified.