As we know Nikola Motors is far from a revenue-generating period, so it would be logical to short.
Based on increasing short volume again - Check Fintel.io And the fact earnings are coming out, we could expect a dip to 13$ or below.
Personally, I think this is a good play and overvalued IMO so correction is inevitable. Didn't pay much attention to the scandal last year but we seem to be due for a drop.