I think you changed the mode in your Latin translation. Your Latin says (as far as I can tell) "Glycon defends us ...", instead of "Glycon defend us ..." which would be "Glycon defende nos ...". I can’t tell anything about "pestilentia nubibus", I don’t know Latin well enough.
Anyhow, using Latin it sounds even more like you’re advertising for a cult and spreading prayers.
I think you're right. I don't know much Latin... Them it would be even closer to Portuguese:
"
Glycon defende nos pestilentia nubibus"
But I found that you could also have: "
Glycon pestilens tueantur nubibus".
I don't know enough to tell which is more appropriate in that context. I'm using my vague knowledge together with an dictionary
Pestilentia=plague,
Pestilens=pestilential, unhealthy, unwholesome,
tueantur=to guard, defend, protect,
nubibus=clouds (plural, sing:
nubes)
And yes, the idea here would be advertising for a cult as Wyrm suggested
Now to find a suitable cave to hold the secret meetings...