"In this way we can help" is right, but "we can help in this way" isn't?
Because Duolingo doesn't have it in its database, that's why you should use the report button and report such stuff, so that the team can add it.
As far as I know they must be written differently:
"Wir können auf diese Weise helfen"
Nope. Both word orders "Wir können auf diese Weise helfen." and "Auf diese Weise können wir helfen." work.
[From TFD:] manner =
'1. A way of doing something or the way in which a thing is done or happens
'2. A way of acting; bearing or behavior
No, it's even fine without object at all: Wir können helfen. Ich helfe gerne.
Of course if you want to express "to help someone", then it's "jemandem helfen", dative.
I thought that it isn't the verb "helfen" but rather the preposition "auf" that here would determine the Dativ: ... auf dieser Weise helfen ...
No, "deshalb" means "therefore", "hence", which does not have the same meaning as "in that way"/"auf diese Weise".
Why does können come before wir? Wouldnt that mean 'In this way, can we help?'
And seeing as im most certainly wrong, how would you say 'can we help in this way?'
In a declarative sentence the conjugated verb must be in the 2nd position in German (1st pos: "Auf diese Weise"). You could, however, also say "Wir können auf diese Weise helfen".
In a question, however, it would be "Können wir auf diese Weise helfen?".