13:13 Feb 6 

"By" or "by way of" are how I would put it. You could consider rewriting the sentence to "Hovedinntrykket er at det har blitt sendt et signal gjennom norske myndigheter, media og spillselskapene selv om at de aktuelle pengespilltilbudene ikke er regulert av norske myndigheter." I would also say "the gaming companies themselves"

08:36 Feb 6 

One possibility is that the author had second thoughts about the use of preposition and the phrase norske myndigheter sneaked in twice. It is something worth considering, especially if the general quality of the text is not very good.