I saw this someone but have searched on google to affirm or deny it, but didnt find anything on all nerves ending in the tongue. Please help
No, nerve endings are where they communicate with muscles (motor nerves) or the ends are where information is sensed, like touch or taste (https://en.wikipedia.org/wiki/Free_nerve_ending).
You could probably say that all nerves start in the brain but they spread out and end everywhere. http://www.innerbody.com/image/nervov.html
No all nerves do not innervate the tongue.
Out of the 12 pairs of cranial nerves only three nerves innervate the tongue; the pharyngeal part of the tongue is supplied by the glossopharyngeal nerve (IX) and the oral part is suppled by the lingual nerve [a branch of the mandibular branch (V3) of the trigeminal nerve (V)] and by the chorda tympani [a branch of the facial nerve(VII)]. Apart from them the intrinsic and extrinsic muscles of tongue is supplied by Hypoglossal (XII).
The rest of the eight nerves along with C.N IX, V and VII have different extracranial destinations.
For e.g.- The first cranial nerve originating from olfactory bulb of fore brain reach the olfactory mucosa in the upper part of the nasal cavity.
P.S. To understand the extracranial course of cranial nerves read this wikipedia page.
Besides here's a diagram that roughly illustrates the major areas of innervation of Cranial nerves.