So I'm not exactly sure what I did here, but I have this:
So first I started by going to the values you specified, 0x22BC4 and 0x22BD4. Both Hex values there were 04, like what is found in the other GBA FE games, so I changed those both to 0A. Now I knew this alone wouldn't solve the problem, as you said, so I looked around for what else I could find.
I came upon 0x22EAC
08022EAC 2809 CMP r0, #0x5 //Scope of support@ADDRESS
08022EAE DC27 BGT #0x8022F00
08022EB0 202C MOV r0, #0x2C
08022EB2 89A9 LDRH r1, [r5, #0xC]
08022EB4 4008 AND r0 ,r1
08022EB6 2800 CMP r0, #0x0
08022EB8 D122 BNE #0x8022F00
08022EBA 6838 LDR r0, [r7, #0x0]
08022EBC 7901 LDRB r1, [r0, #0x4]
08022EBE 1C28 MOV r0 ,r5
08022EC0 F7FF FEB2 BL 0x08022C28
The Hex value stored at that address was 03. I tried bumping it up to 05, and suddenly Roy is able to have 3 B supports and 1 C support. 7 Conversations worth. However, vexingly enough, Alan and Lance still maxed out (glowing text) at One A support and one B support, like normal. And then upon trying to do this a second time, Roy got stuck at two B supports and two C supports, and then oculdn't start any more conversations.
I am not exactly certain that I have found the right value to mess with, but considering that tweaking 22EAC allowed me to go beyond 5 support conversations with Roy, I think I might be on to something. Unfortunately, I'm a total novice, so I don't know what to do from here. Do you have any ideas?