I did nearly the same mistake with Foluu's ones by pressing the protector itself.Just installed the Whitestone dome protector. A lot of steps but pretty foolproof. Applied perfectly and my fingerprint reader still works fine. Just make sure to wipe up any excess liquid after the first curing step. I think I tilted it a bit too much because it was all over but wiped up easily with some rubbing alcohol and the masking stickers they provide prevented it from getting in any buttons or holes.
But five days ago, I had the time to tru the second glass they delivered in the package : I simply just empty the whole seringe, then put and adjust the tempered glass on it. Once every part of the glue was present everywhere, which can be easily seen when offscreen, I immediatly started the UV drying.
Compared to my first try it is faaaaaaaaaaaaar better concerning finitions. I just have a very little leak that appeared on the drying process, but 99% of the liquid have been used and perfectly glued with it.
The result after 5 days is really better than my first try. I just have the extrem edge of the tempered glass where I can see that the glue isn't in place like at the very first time, but I assume the O+ case is the culprit here : it's just edge to edge with the protection which surelly make the glue not very effective, but the finition is now top notch!!