Looking at CapFriendly, I'm pretty sure I have this correct.
Going into the final weeks the Oil have $226,408 in cap space left. It costs...
View attachment 837963
... for
every day that each of those guys are on the roster). The season ends on the April 18th.
There is no 23 man roster limit, just what you can fit under the cap. But teams only get
4 (regular) recalls after the TDL.
Holloway and Broberg can be recalled and sent down without issue; Plus with Vinny injured, I believe Broberg can count as an emergency recall.
Campbell, you can re-waive without fear of losing. But I imagine Lavoie would be a one-way trip up, as he would risk getting claimed. The same situation as Pickard.
The Oil close out the season with 3 games: the 15th @ SJ, the 17th vs. ARI, and the 18th vs. COL). In theory, they could recall all 4 on the 14th and would be able to fit everyone under the cap.