Sorry!!! I should have trusted LEDE to be working perfect and myself being capable of port forwarding.
It's the Foscam camera Certificate that's not valid anymore. Valid until 7 december 2016.
And the iPhone i was using to test, kept the old certificate and thus simply refusing the connection without telling me it's the certificate. I only saw:"can't connect" since I changed everything just this week, I thought it must be my settings. But this is just a bad coincidence the foscam certificate to become outdated.
So everything works! Just had to reset my iphone certificates.
stupid iPhone not telling me the certificate isn't valid anymore and not asking me for an exception..
and stupid foscam their certificates wearing out within 12 months after my purchase.
Next time I switch from DD-WRT to LEDE i better "reset" my testing devices .. learned one more valuable lesson.