why is it dangerous for Lloyd to move back to the UK?
Firstly living cost is the UK isn't the same as in Croatia. Whatever sum of dollars he's getting from patrons and youtube it would have a different value if he lived in the UK. Travelling costs, rent, food, inflation you name it.
He has always been against Brexit. Whatever political ideas we are standing at the moment the economy in the UK is in a bad shape. It may improve and surely it will but no indications so far that this will be happening within a short run.
With his allergy for a decent, paid job, Croatia at the moment offers him a financial stability he wouldn't otherwise have in the UK.
Secondly, as LMsA reported recently his story about his JC and escape from the UK has inconsistencies and contradictions due to the fact that a serious occurrence happened in Bramhall that led to Lloyd fleeing the UK. How serious? Enough to concern a Croatian elder sometime later (he speaks about this in his book). Likely Evans papa organised everything to avoid more serious consequences. Pay attention though that Lloyd is a known liar and a manipulator. He may have changed timeline of events in his story, people etc., But there are people who know the details of what happened. Coming to the UK would be very risky because JWs can become EXJWs and are not longer subject to WT privacy policies. There is the possibility that some of the people involved may speak out at some point.
This would apply to Dijana too. She knows many things and may have decided to stay silent for some reasons. Being close to Dijana is crucial at this stage.