Can't redeem Gold Xbox 360 games in my Xbox One

It has always been like that not unless there will be an update regarding in redeeming Xbox 360 games with gold on the website. Xbox 360 marketplace has a different structure than on Xbox One Store. Xbox 360 games with gold on the website will need a payment
method. In Xbox 360 console, you won't need one. Currently, you can't redeem Xbox 360 games with gold using Xbox One console and still under progress about redeeming Xbox 360 games with gold on Xbox One console. Either get the games using an Xbox 360 console,
or get the games on the website with a payment method.

That's your mistake

Redeeming an 14 day gpld trial enables only full gold on xbox one for 2 weeks

However on 360 it has restrixtions including game ones

If you had redeemed it on xbox 360 it wouldn't be an issue

As you would.be within the limits of the 360 and the trial

But since you redeem it on the one you can't as it's non restricted which is not compatible with 360

Xbox One games with gold are usable by you when you have an active gold subscription and have redeemed them. If your subscription ends, you will have to buy the game or resubscribe to xbox live gold to use them again. There is no
way to redeem a past xbox live game with gold when it is no longer available for redemption.

Xbox 360 games with gold are different - you own those whether you have xbox live gold or not - on xbox one and xbox 360.

I can't transfer from xbox 360 gold free games from my xbox one. just from the site, i've made it on xbox 360 gold on dirt 3, but i can't with Dungeon Siege III

If you do get an Xbox Live Gold membership for your Xbox 360 don't forget each month to redeem the Games WIth Gold games for both the Xbox 360 and Xbox One, this way if you do purchase an Xbox One at a later stage as long as you still have an active Gold
subscription the Xbox One games will be available for you to download and play in addition to the Xbox 360 games.