well
Slightly warm to us is hotter to them.....so thawed in lukewarm should be fine, I just use warmer water while they are sitting waiting to be fed off. Lukewarm water is fine, like room temp water, which is already 70-80 degrees.
Water that feels hardly warm to us can be much to hot for a snake so you have to be kinda be careful, but if you use regular lukewarm/room temp water you won't have problems. If you are worried about it being totally thawed in lukewarm water, then just thaw it for a bit longer, it won't hurt.
bmm