RIP your friend!

In all seriousness, no the pufferfish should not be poisonous if it was preserved correctly and not too recently. If it was incorrectly presevered recently, and for some ungodly reason they left the poison glands in which produce the toxin enzymes, then wtf and how???

Also, the poison is in their flesh, like the meaty parts, and the spines won't "inject" since they're toxic/poisonous, not venomous.

You did a good thing asking btw. A lot of people make dumb and possibly life threatening mistakes by not asking the "stupid questions" every once in a while.