oh sorry to hear that you cannot have the Ticino ticket offer. in my personal opinion it should have been given to ppl who paid the tourist tax to the canton. But I am not running a hotel or bnb so I cannot comment too much on it.
I am happy you liked the recommendation of the old Gotthard route. I just wanted to add some more fact about it. The Gotthard panoramic express you were checking is a special train aimed for tourists, it will be shown on SBB’s app with a PE sign, it is a 1st class only service with a mandatory surcharge on seat reservation. if you are okay with it the experience is of course superb. otherwise I recommend you to check the IR train departing from Locarno (passing through Bellinzona, if you will be from Lugano direction you will most likely change at Bellinzona) by südostbahn, branded as Treno Gottardo, on SBB’s app they are shown as IR trains (inter regio), directing to Zuerich HB or Basel SBB. They are more frequent, they pass through all the stops included in the PE service (hourly service, in comparison I think here are only two PE service daily for Lugano) and the train is simply modern and comfy, with onboard self service bistro.
Another little fact I want to add. Without the possibility of “free” travel card by your bnb you will just buy ticket to move around Ticino (as I assume your first days will be mainly in this canton) You can simply use the easy ride function in the SBB app. the reason is that the transportation fare in canton of Ticino and little part of canton of Graübuden (or Grisons), namely the valley Moesa, is standardised in a fare system by zones called Arcobaleno and here is no super saver tickets in this system, and you cannot pay more than 38 CHF (the cost of all zone day pass, without HFC, with half fare it is of course 19 CHF) a day within this zoning system. check this for the map of the zone system check this for the pricing. With easy ride you can just swipe left to check in before you start your journey and swipe right every time you finish your journey. the app will calculate automatically the lowest fare for you, so you don’t need to think about ticketing.