dmikefer;
Your neighbor has no responsibility for your property unless he/she agrees to take responsibility. You may be pissed, but legally, you can cut the roots, fix the foundation or otherwise correct the situation. Your neighbor has no legal responsibility.
You cannot, however, cross the property line to correct the situation, hence my VERY FIRST response to you to cut the roots.
If you want to play games with this idiot Florida, if you want to listen to his ramblings and assertions, be my guest. But be warned, if you do continue in dialogue with him you will likely NOT receive another response from me or any other responsible, knowledgable person on this forum.
And before you decide, go here and read this 'person's' depth of knowledge and legal reasoning.
https://forum.freeadvice.com/showthread.php?t=205953
I am done with him. And with any luck, so is this forum.