@DoubleTweenQueen
You may have the day off work but I don't! So forgive me if I can't go into the detail that you might hope for.
'Thwarted belongness' which you refer to in point 2 - I imagine this would relate to the extent to which the young person feels accepted and recognised in their stated gender ID.
'Environmental stressors' and 'destigmatization of noncisgender identities' again these issues likely relate to the degree of acceptance felt by a person in their identity, so for eg. not being welcome in the toilet matching your gender ID, refusal of parents / teachers to acknowledge your gender ID, operating in a culture where trans /non-binary IDs are frowned upon.
Abstracts will provide you with a good summary of research, but yes, to examine in detail you will need to access the full texts, can't help you there, sorry.
It's good to examine research thoroughly, but it's also important to bear in mind over-arching themes that are developing out of research.
Take studies into Covid, for example. There will be many, many studies out there that showing the effectiveness of vaccines. But some of them will have problems with them, others may say unusual things that go against the main body of evidence, others will indeed highlight issues that need to be examined further. But taken as a whole what is the overall picture? How do you choose to process that information?
There are of course people who choose to ignore the main body of information and evidence and focus solely on those less well-thought of studies telling them what they want to hear, because it justifies their preconceptions, biases and behaviours and allows them refuge from cognitive dissonance.
I think it's important to consider the evidence as a whole; there is not a study out there that can not be nit-picked away by someone so minded.