Ok, of course I was not paying enough attention, the first error was due to the fact that I could not insert the SSID it needed to be converted to a string (this does not make so much sense to me as the type was a string but it did solve the problem.
The arp request was also a simple solve, to get arp requests the sniffer should not put the wifi into monitor mode, as it was set in the examples.
Just in case someone else tries to do the same.
Fred