In Eberron, it’s possible for a character to be a member of two or more Guilds?

TL;DR: A character who is a member of the Blademarks Guild of House Deneith was invited to join the Clifftop Adventures’ Guild and he accepted, will there be any consequences for him?

Detailed Question:

I’m running a campaing in the setting of Eberron, using the Rising From the Last War as a guiding to the setting. My idea is that the players eventually join the Clifftop Adventurers’ Guild.

But one of the the players made a human fighter who is from Karrnath who, for personal reasons, joined the Blademarks Guild of House Deneith. He is not a dragonmarked character, he is just a fighter who sell his sword to the Guild.

Now, as a reason for him to go to Sharn, I said that he is receiving few jobs from the guild in Karrnath and wants to see if the guild branch in Sharn has more services for him. I recently run the first session where they helped a villager, and a member of the Clifftop Guild became admired with the party display of autruism and strengh, and he invited them to join the guild. The players accepted the invitation, but afterwards I started to wonder how this would play with that character relationship with the Blademarks Guild

Are there any explicts impeditive for him to join the Clifftop Guild?

Does he needs to choose between one guild or other, or he can be a member of both guilds and take job from them as he wishes?

Since he is not a dragonmark character, I thought that he’s relationship with the guild was more flexible, but I didn’t find any source that could provide more details about these relationships between a guild and they members.

If possible, I wanted to clear these questions:

  • Can he be a member of both guilds?
  • If not, will the Blademarks Guild recent him if he chooses the Clifftop over them?