[partly confirm]Ishai & Tymna crash on cast with partner

[drool66]

Describe the Bug:
Ishai, Ojutai Dragonspeaker and Tymna the Weaver crash on cast when used with a partner. They do not crash when used as a sole commander.

Which card did behave improperly?
Ishai, Ojutai Dragonspeaker and Tymna the Weaver, maybe the EDH rules card

Which update are you using? (date, name)Which type? (duel, gauntlet, sealed deck)
Manalink dev 778ccb5 version - duel

What exactly should be the correct behavior/interaction?
These commanders can be cast normally

Are any other cards possibly affected by this bug?
While I didn't test all 91 combinations of partners, I tested each commander with at least one other partner. The rest seemed to work fine, and it doesn't seem to depend on which commander they're paired with. For example, if you have Ishai or Tymna as one commander, but only have mana open for your other commander (Tana, the Bloodsower, for example), you can cast your other commander with no problem.

[Aswan jaguar]

How many cards/generals/edh you use for edh partner because I always get illegal number of cards?

[drool66]

You need 103 total: 98 + 1 EDH + 2 Commander A + 2 Commander B

[Aswan jaguar]

It doesn't seem to be anything special about these cards.It seems that all cards with partner in edh if there is enough mana to cast them as generals both in same turn or something like that then game crashes.

Edit: some more testing shows more problems or the same:In the screenshot below I have mana to cast as general either Tymna the Weaver or Ishai, Ojutai Dragonspeaker.I click on edh card and you can see that menu where it should say Ishai, Ojutai Dragonspeaker has 3 weird characters but the biggest problem seems that when you select Tymna the Weaver you have to pay Ojutai cost and vice versa.

[drool66]

Thanks for looking into this. Ya, I'm still trying to figure out how that menu works - if you have mana open to cast either commander you'll often have to do things like cancel out, reselect, and select that you're casting one in order to cast the other. But still after trying it over and over again, activating the command zone with mana open to cast Tymna or Ishai will unconditionally CTD for me regardless of what I've done with the other commander; whereas I've had no issues with any others. Albeit, I haven't tested every other one as extensively as these two. The difference could be my setup - I'm running on Windows 10.
I'll see if I can gather any more information.