I wonder if lerya- 'release, set free' is the right word here. ("I won't release whoever walks through my mind..." ?). Could váquet- work ('say no to' = 'not allow')?

Hm, you may be right, lerya- is not a good choice. Váquet- is much better. (I have been contemplating lav- as well but that one's not as clear-cut as váquet-).

I think the main problem with lav- is that a homonym means 'lick'.

It is a problem, but still the word is too 'valuable' just to let it lie around unused:) It could yield (pun intended) so many senses: give up, surrender, allow to do sg, etc...