As for your particular questions, I know for sure that Gobbi has a bad rep, and it would seem that many of the others you name are also hinky; . I donāt know much about the Catholic Doors site, but
their info on these folks seems fairly good in its criticisms.
Catholic Planet has some criticisms of Villavicencioās vision messages and circumstances, which are also worth considering. (Of course, sites not run by the Church may have criticism that isnāt entirely accurate, too, so read with a grain of salt.) Didnāt find anything in particular about Centelli, but itās hinky that sheās had four volumes of her revelations published without getting a bishopās approval. I wouldnāt touch any of these people with a ten foot pole, frankly.
More to the point, none of these folksā private revelations seem to be approved. So why did the book writer put out a book about them?
First off, thereās absolutely nothing in any private revelation that you
need to know. None of it is necessary to your salvation. I love Fatima and Lourdes and all the rest, but their place in the plan of salvation is much lower than Sunday Mass with the cruddiest celebration by the skankiest priest. (Albeit Fatima and Lourdes can be a lot more helpful in showing us the plan of salvation, in a way that we can openly understand.)
Second, you really should be spending your attention only on private revelations that have been approved by their local bishop. Most dioceses have websites that talk about any local visionaries that have been approved. The same thing is true of real religious orders with visionary members, etc. If you donāt see anything, be cautious. If a private revelation is still under investigation, that doesnāt mean itās approved.
Third, private revelations donāt have to be disapproved to be not okay to spread around. In fact, unless private revelations have been approved in some way, theyāre not really supposed to be spread around. Unless the message of the revelations has an imprimatur or at least a nihil obstat, you should be very very skeptical that the revelations are even orthodox in their theology, much less authentic.
Fourth, itās okay to have some idle curiosity. I have plenty myself. Conversion stories and stories of signs and wonders are very nice. And sure, some private revelations will eventually be approved, and probably arenāt harmful now. But in these matters, the bishops are like our parents, and we should honor their decisions and authority over us.
Fifth, if you find yourself worrying about this stuff, you need to stop reading accounts of unapproved revelations and start doing something spiritually useful.
Be not afraid. Follow Godās ordinary commands to us, go to Mass, pray, fast sanely, give alms and help to those who need it. Thatās all you need to know.
Not really sure if I have included this on the right part of the forum. 
