Could you check this over

I don't know much about Sanskrit so I can't help you there.

I don't find *wh₁itéy- very convincing as the origin of the Balto-Slavic forms, personally. The long vowel can be explained, in general, as either from a following laryngeal or from the new length ablaut. However, such new long vowels were always used in specific derivational processes that were innovated within Balto-Slavic, and I find it very unlikely that an old formation like a ti-stem would have such a long vowel. What also needs to be considered is that ti-stems became productive as infinitives in Balto-Slavic, so if one of them happened to survive as a noun, it must be an archaism and thus can't be an innovated derivation at the same time.