Actually, that does ring a bell. I guess the team could always just cut him, but for now I think you're right and he is under contract on a two-way.
So the situation appears to be:
12 players signed to guaranteed deals:
C: Holmes, Whiteside
PF: Bagley, Bjelica, Parker
SF: Barnes, Jeffries
SG: Hield, Haliburton, James
PG: Fox, Joseph
1 player signed to a two-way deal:
Guy
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2 unsigned second-round draft picks:
Woodard
Ramsey
1 unguaranteed contract
Kaminsky
1 Exhibit 10 contract
Rose
1 camp invite
Metu
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That means right now we have five players competing for four slots (three NBA roster slots and a two-way slot). The leader for the two-way slot right now would appear to be Quinton Rose. The Exhibit 10 contract gives us the option to convert the deal to a two-way before the season starts. However, we've likely added an Exhibit 10 bonus which would allow us to cut him outright and give him up to a $50K bonus if he signs with our G-League team. This would allow us to "stash" him in Stockton without using a two-way, (but he would be liable to be poached by another team with a guaranteed NBA contract).
This flexibility is important because we will probably want control of three players, and we only have three roster slots. Kaminsky is likely to stick, and Woodard is likely to get an NBA deal, so that would bring us to 14 players. Ramsey would be the logical choice for the 15th player, but we might decide to go with Metu (or another future camp invite), or we might execute a trade that brings back an additional player, in which case we'd need to put Ramsey into the two-way slot, and Rose would likely be the one cut because we'd retain some measure of team control of him.
Needless to say, we don't have a lot of room to play around with, and it's not out of the question that future moves might necessitate us cutting a player to gain another NBA slot (Kaminsky, James, Parker most likely?) or a two-way slot (Guy).