Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
It seems that (to sum up) the iPhone and the iPad and the TV can enter the WiFi passphrase properly, but the other devices (printer, WiFi thermostats) cannot.
It also seems to me that you are saying that the password ***** the new router's configuration / setup is not being accepted. Is that the case?
A problem there might be, that you are trying to access the setup by wireless. This is disabled on some routers, either as a default or as a configured measure that increases security. You may well have to connect to it with a cable, e.g. Ethernet cable, to use the router box's setup utility. That might perhaps be done from the TV, if it is a 'smart TV' with an Ethernet port. But otherwise, yes, a computer would be needed.
OK. I hope my advice helps. If you need assistance with further details, let me know.
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