One obstacle would might be security concerns if Pelco is bought by a Chinese company. I'm sure Pelco is on a lot of government bid and procurement sheets- that might change if Dahua bought them given all the cyber security concerns between the US and China that has been in the news lately.
China reacts furiously to US cyber-espionage charges
Chinese attempts to buy Amercian security related companies or to sell technology to American companies have been held up or blocked in the past.
Sprint won't use Huawei gear, says lawmaker