The only thing is that the communities are established.
Paul though talks about 500 witnesses available for consultation.
The 500 people claim really undermines him. Why - because if 500 people (a significant proportion of the population in those days) had actually seen a person they knew to have died be alive again, that would spread like wildfire. Each person telling perhaps 5 others of friends and family and in a couple of transmission steps much of the population would know. Yet this astonishing 'revelation' lies dormant for decades, and tends to resurface not locally but in distant parts.
So you'd either need to conclude that seeing a dead man alive again was no big deal and therefore not something to become the 'talk of the town'.
Or that it never happened - or that the claim of 500 witnesses at one point is a massive exaggeration aimed at enhancing his claim (but it actually undermining it).
Even if we accept that 500 people thought they saw a dead man alive again, but were mistaken (e.g. because they saw someone who looked like Jesus or he never actually died) it would still surely have become the talk of the town, unless dead people becoming alive again was commonplace - yet there is no evidence whatsoever that the purported resurrection became the 'talk of the town'. And don't try to play the - oh but it would have been only communicated via oral routes. Why because had the 500 told 5 people each and they also told 5 each, we'd have 12,500 people talking about it within hours of days and that would surely have come tot he attention of the authorities, whether Jewish or Roman, who given the political sensitivities would no doubt be interested and probably concerned. They were, of course, assiduous record keepers.