龙舟队分哪个两个组？ is simply incorrect.
The combination of 哪个 and 两个组 doesn't make any sense grammatically and logically.
哪个 means WHICH ONE, for example: A B C D, 哪个是B？(which one is B?). The second one is B.
哪两个组 is right, means WHICH TWO GROUPS?
So the correct sentence is 龙舟队分哪两个组？
分 often comes with 为：
She asked the students to split into groups of four.
Just thinking about a question yesterday on the origin of tense words in Chinese and whether the teams divide themselves or 被分为. Certainly, a team is a team and remains undivided.
The dragon boat teams are divided into which two groups?
Dragon boat ...
I think it is a typo.
remove the extra 个 and write 龙舟队分哪两个组?(dragon boat teams divided into which two groups?) make the most sense
It is wrong to use 个 (a) as a classifier for 两个组 (two groups)
I think this sentence is not perfectly grammatical. You can analyze it as follows:
龙舟队 The Dragon Boat Team
分 (divide into, assign to)
哪个 which (one)
两个组 two groups
It doesn't sound grammatical to me mainly because 哪个 means "哪（一）个 which one", but the subsequent noun phrase is about "两个组 two groups".
We can probably read it as "...