I don't think this is any problem at all because nobody is going to bother making a nesbot fake speedrun TAS. There are 3 reasons for that: 1. It takes the IQ of Einstein to build such a thing. 2. Only an asshole would submit a TAS to SDA as a speedrun. 3. It's not worth the trouble because you don't gain enough from it.
and yet, people have tried submitting TASes to SDA in the past. Reason 1 is disproven because someone could potentially get a NESBot on the internet. Reason 2 is true, but there are such people in the world Reason 3 is subjective, some people would cheat so they can say "oh hai guyz look at my WR" So, though it's likely no one is going to try to submit a NESBot TAS to SDA, it can't hurt to check.
micro500 posted the plans to build your own nesbot. It's very simple assembly of parts. If you're not willing to do that, he's sold a few of them already and would probably sell more if there was a demand.